Adding upstream version 5:7.2.4.upstream/5%7.2.4upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 3257 insertions, 0 deletions

diff --git a/src/quicklist.c b/src/quicklist.c
new file mode 100644
index 0000000..301a216
--- /dev/null
+++ b/src/quicklist.c
@@ -0,0 +1,3257 @@
+/* quicklist.c - A doubly linked list of listpacks
+ *
+ * Copyright (c) 2014, Matt Stancliff <matt@genges.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must start the above copyright notice,
+ *     this quicklist of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this quicklist of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <stdio.h>
+#include <string.h> /* for memcpy */
+#include <limits.h>
+#include "quicklist.h"
+#include "zmalloc.h"
+#include "config.h"
+#include "listpack.h"
+#include "util.h" /* for ll2string */
+#include "lzf.h"
+#include "redisassert.h"
+
+#ifndef REDIS_STATIC
+#define REDIS_STATIC static
+#endif
+
+/* Optimization levels for size-based filling.
+ * Note that the largest possible limit is 64k, so even if each record takes
+ * just one byte, it still won't overflow the 16 bit count field. */
+static const size_t optimization_level[] = {4096, 8192, 16384, 32768, 65536};
+
+/* packed_threshold is initialized to 1gb*/
+static size_t packed_threshold = (1 << 30);
+
+/* set threshold for PLAIN nodes, the real limit is 4gb */
+#define isLargeElement(size) ((size) >= packed_threshold)
+
+int quicklistisSetPackedThreshold(size_t sz) {
+    /* Don't allow threshold to be set above or even slightly below 4GB */
+    if (sz > (1ull<<32) - (1<<20)) {
+        return 0;
+    } else if (sz == 0) { /* 0 means restore threshold */
+        sz = (1 << 30);
+    }
+    packed_threshold = sz;
+    return 1;
+}
+
+/* Maximum size in bytes of any multi-element listpack.
+ * Larger values will live in their own isolated listpacks.
+ * This is used only if we're limited by record count. when we're limited by
+ * size, the maximum limit is bigger, but still safe.
+ * 8k is a recommended / default size limit */
+#define SIZE_SAFETY_LIMIT 8192
+
+/* Maximum estimate of the listpack entry overhead.
+ * Although in the worst case(sz < 64), we will waste 6 bytes in one
+ * quicklistNode, but can avoid memory waste due to internal fragmentation
+ * when the listpack exceeds the size limit by a few bytes (e.g. being 16388). */
+#define SIZE_ESTIMATE_OVERHEAD 8
+
+/* Minimum listpack size in bytes for attempting compression. */
+#define MIN_COMPRESS_BYTES 48
+
+/* Minimum size reduction in bytes to store compressed quicklistNode data.
+ * This also prevents us from storing compression if the compression
+ * resulted in a larger size than the original data. */
+#define MIN_COMPRESS_IMPROVE 8
+
+/* If not verbose testing, remove all debug printing. */
+#ifndef REDIS_TEST_VERBOSE
+#define D(...)
+#else
+#define D(...)                                                                 \
+    do {                                                                       \
+        printf("%s:%s:%d:\t", __FILE__, __func__, __LINE__);                   \
+        printf(__VA_ARGS__);                                                   \
+        printf("\n");                                                          \
+    } while (0)
+#endif
+
+/* Bookmarks forward declarations */
+#define QL_MAX_BM ((1 << QL_BM_BITS)-1)
+quicklistBookmark *_quicklistBookmarkFindByName(quicklist *ql, const char *name);
+quicklistBookmark *_quicklistBookmarkFindByNode(quicklist *ql, quicklistNode *node);
+void _quicklistBookmarkDelete(quicklist *ql, quicklistBookmark *bm);
+
+/* Simple way to give quicklistEntry structs default values with one call. */
+#define initEntry(e)                                                           \
+    do {                                                                       \
+        (e)->zi = (e)->value = NULL;                                           \
+        (e)->longval = -123456789;                                             \
+        (e)->quicklist = NULL;                                                 \
+        (e)->node = NULL;                                                      \
+        (e)->offset = 123456789;                                               \
+        (e)->sz = 0;                                                           \
+    } while (0)
+
+/* Reset the quicklistIter to prevent it from being used again after
+ * insert, replace, or other against quicklist operation. */
+#define resetIterator(iter)                                                    \
+    do {                                                                       \
+        (iter)->current = NULL;                                                \
+        (iter)->zi = NULL;                                                     \
+    } while (0)
+
+/* Create a new quicklist.
+ * Free with quicklistRelease(). */
+quicklist *quicklistCreate(void) {
+    struct quicklist *quicklist;
+
+    quicklist = zmalloc(sizeof(*quicklist));
+    quicklist->head = quicklist->tail = NULL;
+    quicklist->len = 0;
+    quicklist->count = 0;
+    quicklist->compress = 0;
+    quicklist->fill = -2;
+    quicklist->bookmark_count = 0;
+    return quicklist;
+}
+
+#define COMPRESS_MAX ((1 << QL_COMP_BITS)-1)
+void quicklistSetCompressDepth(quicklist *quicklist, int compress) {
+    if (compress > COMPRESS_MAX) {
+        compress = COMPRESS_MAX;
+    } else if (compress < 0) {
+        compress = 0;
+    }
+    quicklist->compress = compress;
+}
+
+#define FILL_MAX ((1 << (QL_FILL_BITS-1))-1)
+void quicklistSetFill(quicklist *quicklist, int fill) {
+    if (fill > FILL_MAX) {
+        fill = FILL_MAX;
+    } else if (fill < -5) {
+        fill = -5;
+    }
+    quicklist->fill = fill;
+}
+
+void quicklistSetOptions(quicklist *quicklist, int fill, int depth) {
+    quicklistSetFill(quicklist, fill);
+    quicklistSetCompressDepth(quicklist, depth);
+}
+
+/* Create a new quicklist with some default parameters. */
+quicklist *quicklistNew(int fill, int compress) {
+    quicklist *quicklist = quicklistCreate();
+    quicklistSetOptions(quicklist, fill, compress);
+    return quicklist;
+}
+
+REDIS_STATIC quicklistNode *quicklistCreateNode(void) {
+    quicklistNode *node;
+    node = zmalloc(sizeof(*node));
+    node->entry = NULL;
+    node->count = 0;
+    node->sz = 0;
+    node->next = node->prev = NULL;
+    node->encoding = QUICKLIST_NODE_ENCODING_RAW;
+    node->container = QUICKLIST_NODE_CONTAINER_PACKED;
+    node->recompress = 0;
+    node->dont_compress = 0;
+    return node;
+}
+
+/* Return cached quicklist count */
+unsigned long quicklistCount(const quicklist *ql) { return ql->count; }
+
+/* Free entire quicklist. */
+void quicklistRelease(quicklist *quicklist) {
+    unsigned long len;
+    quicklistNode *current, *next;
+
+    current = quicklist->head;
+    len = quicklist->len;
+    while (len--) {
+        next = current->next;
+
+        zfree(current->entry);
+        quicklist->count -= current->count;
+
+        zfree(current);
+
+        quicklist->len--;
+        current = next;
+    }
+    quicklistBookmarksClear(quicklist);
+    zfree(quicklist);
+}
+
+/* Compress the listpack in 'node' and update encoding details.
+ * Returns 1 if listpack compressed successfully.
+ * Returns 0 if compression failed or if listpack too small to compress. */
+REDIS_STATIC int __quicklistCompressNode(quicklistNode *node) {
+#ifdef REDIS_TEST
+    node->attempted_compress = 1;
+#endif
+    if (node->dont_compress) return 0;
+
+    /* validate that the node is neither
+     * tail nor head (it has prev and next)*/
+    assert(node->prev && node->next);
+
+    node->recompress = 0;
+    /* Don't bother compressing small values */
+    if (node->sz < MIN_COMPRESS_BYTES)
+        return 0;
+
+    quicklistLZF *lzf = zmalloc(sizeof(*lzf) + node->sz);
+
+    /* Cancel if compression fails or doesn't compress small enough */
+    if (((lzf->sz = lzf_compress(node->entry, node->sz, lzf->compressed,
+                                 node->sz)) == 0) ||
+        lzf->sz + MIN_COMPRESS_IMPROVE >= node->sz) {
+        /* lzf_compress aborts/rejects compression if value not compressible. */
+        zfree(lzf);
+        return 0;
+    }
+    lzf = zrealloc(lzf, sizeof(*lzf) + lzf->sz);
+    zfree(node->entry);
+    node->entry = (unsigned char *)lzf;
+    node->encoding = QUICKLIST_NODE_ENCODING_LZF;
+    return 1;
+}
+
+/* Compress only uncompressed nodes. */
+#define quicklistCompressNode(_node)                                           \
+    do {                                                                       \
+        if ((_node) && (_node)->encoding == QUICKLIST_NODE_ENCODING_RAW) {     \
+            __quicklistCompressNode((_node));                                  \
+        }                                                                      \
+    } while (0)
+
+/* Uncompress the listpack in 'node' and update encoding details.
+ * Returns 1 on successful decode, 0 on failure to decode. */
+REDIS_STATIC int __quicklistDecompressNode(quicklistNode *node) {
+#ifdef REDIS_TEST
+    node->attempted_compress = 0;
+#endif
+    node->recompress = 0;
+
+    void *decompressed = zmalloc(node->sz);
+    quicklistLZF *lzf = (quicklistLZF *)node->entry;
+    if (lzf_decompress(lzf->compressed, lzf->sz, decompressed, node->sz) == 0) {
+        /* Someone requested decompress, but we can't decompress.  Not good. */
+        zfree(decompressed);
+        return 0;
+    }
+    zfree(lzf);
+    node->entry = decompressed;
+    node->encoding = QUICKLIST_NODE_ENCODING_RAW;
+    return 1;
+}
+
+/* Decompress only compressed nodes. */
+#define quicklistDecompressNode(_node)                                         \
+    do {                                                                       \
+        if ((_node) && (_node)->encoding == QUICKLIST_NODE_ENCODING_LZF) {     \
+            __quicklistDecompressNode((_node));                                \
+        }                                                                      \
+    } while (0)
+
+/* Force node to not be immediately re-compressible */
+#define quicklistDecompressNodeForUse(_node)                                   \
+    do {                                                                       \
+        if ((_node) && (_node)->encoding == QUICKLIST_NODE_ENCODING_LZF) {     \
+            __quicklistDecompressNode((_node));                                \
+            (_node)->recompress = 1;                                           \
+        }                                                                      \
+    } while (0)
+
+/* Extract the raw LZF data from this quicklistNode.
+ * Pointer to LZF data is assigned to '*data'.
+ * Return value is the length of compressed LZF data. */
+size_t quicklistGetLzf(const quicklistNode *node, void **data) {
+    quicklistLZF *lzf = (quicklistLZF *)node->entry;
+    *data = lzf->compressed;
+    return lzf->sz;
+}
+
+#define quicklistAllowsCompression(_ql) ((_ql)->compress != 0)
+
+/* Force 'quicklist' to meet compression guidelines set by compress depth.
+ * The only way to guarantee interior nodes get compressed is to iterate
+ * to our "interior" compress depth then compress the next node we find.
+ * If compress depth is larger than the entire list, we return immediately. */
+REDIS_STATIC void __quicklistCompress(const quicklist *quicklist,
+                                      quicklistNode *node) {
+    if (quicklist->len == 0) return;
+
+    /* The head and tail should never be compressed (we should not attempt to recompress them) */
+    assert(quicklist->head->recompress == 0 && quicklist->tail->recompress == 0);
+
+    /* If length is less than our compress depth (from both sides),
+     * we can't compress anything. */
+    if (!quicklistAllowsCompression(quicklist) ||
+        quicklist->len < (unsigned int)(quicklist->compress * 2))
+        return;
+
+#if 0
+    /* Optimized cases for small depth counts */
+    if (quicklist->compress == 1) {
+        quicklistNode *h = quicklist->head, *t = quicklist->tail;
+        quicklistDecompressNode(h);
+        quicklistDecompressNode(t);
+        if (h != node && t != node)
+            quicklistCompressNode(node);
+        return;
+    } else if (quicklist->compress == 2) {
+        quicklistNode *h = quicklist->head, *hn = h->next, *hnn = hn->next;
+        quicklistNode *t = quicklist->tail, *tp = t->prev, *tpp = tp->prev;
+        quicklistDecompressNode(h);
+        quicklistDecompressNode(hn);
+        quicklistDecompressNode(t);
+        quicklistDecompressNode(tp);
+        if (h != node && hn != node && t != node && tp != node) {
+            quicklistCompressNode(node);
+        }
+        if (hnn != t) {
+            quicklistCompressNode(hnn);
+        }
+        if (tpp != h) {
+            quicklistCompressNode(tpp);
+        }
+        return;
+    }
+#endif
+
+    /* Iterate until we reach compress depth for both sides of the list.a
+     * Note: because we do length checks at the *top* of this function,
+     *       we can skip explicit null checks below. Everything exists. */
+    quicklistNode *forward = quicklist->head;
+    quicklistNode *reverse = quicklist->tail;
+    int depth = 0;
+    int in_depth = 0;
+    while (depth++ < quicklist->compress) {
+        quicklistDecompressNode(forward);
+        quicklistDecompressNode(reverse);
+
+        if (forward == node || reverse == node)
+            in_depth = 1;
+
+        /* We passed into compress depth of opposite side of the quicklist
+         * so there's no need to compress anything and we can exit. */
+        if (forward == reverse || forward->next == reverse)
+            return;
+
+        forward = forward->next;
+        reverse = reverse->prev;
+    }
+
+    if (!in_depth)
+        quicklistCompressNode(node);
+
+    /* At this point, forward and reverse are one node beyond depth */
+    quicklistCompressNode(forward);
+    quicklistCompressNode(reverse);
+}
+
+#define quicklistCompress(_ql, _node)                                          \
+    do {                                                                       \
+        if ((_node)->recompress)                                               \
+            quicklistCompressNode((_node));                                    \
+        else                                                                   \
+            __quicklistCompress((_ql), (_node));                               \
+    } while (0)
+
+/* If we previously used quicklistDecompressNodeForUse(), just recompress. */
+#define quicklistRecompressOnly(_node)                                         \
+    do {                                                                       \
+        if ((_node)->recompress)                                               \
+            quicklistCompressNode((_node));                                    \
+    } while (0)
+
+/* Insert 'new_node' after 'old_node' if 'after' is 1.
+ * Insert 'new_node' before 'old_node' if 'after' is 0.
+ * Note: 'new_node' is *always* uncompressed, so if we assign it to
+ *       head or tail, we do not need to uncompress it. */
+REDIS_STATIC void __quicklistInsertNode(quicklist *quicklist,
+                                        quicklistNode *old_node,
+                                        quicklistNode *new_node, int after) {
+    if (after) {
+        new_node->prev = old_node;
+        if (old_node) {
+            new_node->next = old_node->next;
+            if (old_node->next)
+                old_node->next->prev = new_node;
+            old_node->next = new_node;
+        }
+        if (quicklist->tail == old_node)
+            quicklist->tail = new_node;
+    } else {
+        new_node->next = old_node;
+        if (old_node) {
+            new_node->prev = old_node->prev;
+            if (old_node->prev)
+                old_node->prev->next = new_node;
+            old_node->prev = new_node;
+        }
+        if (quicklist->head == old_node)
+            quicklist->head = new_node;
+    }
+    /* If this insert creates the only element so far, initialize head/tail. */
+    if (quicklist->len == 0) {
+        quicklist->head = quicklist->tail = new_node;
+    }
+
+    /* Update len first, so in __quicklistCompress we know exactly len */
+    quicklist->len++;
+
+    if (old_node)
+        quicklistCompress(quicklist, old_node);
+
+    quicklistCompress(quicklist, new_node);
+}
+
+/* Wrappers for node inserting around existing node. */
+REDIS_STATIC void _quicklistInsertNodeBefore(quicklist *quicklist,
+                                             quicklistNode *old_node,
+                                             quicklistNode *new_node) {
+    __quicklistInsertNode(quicklist, old_node, new_node, 0);
+}
+
+REDIS_STATIC void _quicklistInsertNodeAfter(quicklist *quicklist,
+                                            quicklistNode *old_node,
+                                            quicklistNode *new_node) {
+    __quicklistInsertNode(quicklist, old_node, new_node, 1);
+}
+
+#define sizeMeetsSafetyLimit(sz) ((sz) <= SIZE_SAFETY_LIMIT)
+
+/* Calculate the size limit or length limit of the quicklist node
+ * based on 'fill', and is also used to limit list listpack. */
+void quicklistNodeLimit(int fill, size_t *size, unsigned int *count) {
+    *size = SIZE_MAX;
+    *count = UINT_MAX;
+
+    if (fill >= 0) {
+        /* Ensure that one node have at least one entry */
+        *count = (fill == 0) ? 1 : fill;
+    } else {
+        size_t offset = (-fill) - 1;
+        size_t max_level = sizeof(optimization_level) / sizeof(*optimization_level);
+        if (offset >= max_level) offset = max_level - 1;
+        *size = optimization_level[offset];
+    }
+}
+
+/* Check if the limit of the quicklist node has been reached to determine if
+ * insertions, merges or other operations that would increase the size of
+ * the node can be performed.
+ * Return 1 if exceeds the limit, otherwise 0. */
+int quicklistNodeExceedsLimit(int fill, size_t new_sz, unsigned int new_count) {
+    size_t sz_limit;
+    unsigned int count_limit;
+    quicklistNodeLimit(fill, &sz_limit, &count_limit);
+
+    if (likely(sz_limit != SIZE_MAX)) {
+        return new_sz > sz_limit;
+    } else if (count_limit != UINT_MAX) {
+        /* when we reach here we know that the limit is a size limit (which is
+         * safe, see comments next to optimization_level and SIZE_SAFETY_LIMIT) */
+        if (!sizeMeetsSafetyLimit(new_sz)) return 1;
+        return new_count > count_limit;
+    }
+
+    redis_unreachable();
+}
+
+REDIS_STATIC int _quicklistNodeAllowInsert(const quicklistNode *node,
+                                           const int fill, const size_t sz) {
+    if (unlikely(!node))
+        return 0;
+
+    if (unlikely(QL_NODE_IS_PLAIN(node) || isLargeElement(sz)))
+        return 0;
+
+    /* Estimate how many bytes will be added to the listpack by this one entry.
+     * We prefer an overestimation, which would at worse lead to a few bytes
+     * below the lowest limit of 4k (see optimization_level).
+     * Note: No need to check for overflow below since both `node->sz` and
+     * `sz` are to be less than 1GB after the plain/large element check above. */
+    size_t new_sz = node->sz + sz + SIZE_ESTIMATE_OVERHEAD;
+    if (unlikely(quicklistNodeExceedsLimit(fill, new_sz, node->count + 1)))
+        return 0;
+    return 1;
+}
+
+REDIS_STATIC int _quicklistNodeAllowMerge(const quicklistNode *a,
+                                          const quicklistNode *b,
+                                          const int fill) {
+    if (!a || !b)
+        return 0;
+
+    if (unlikely(QL_NODE_IS_PLAIN(a) || QL_NODE_IS_PLAIN(b)))
+        return 0;
+
+    /* approximate merged listpack size (- 7 to remove one listpack
+     * header/trailer, see LP_HDR_SIZE and LP_EOF) */
+    unsigned int merge_sz = a->sz + b->sz - 7;
+    if (unlikely(quicklistNodeExceedsLimit(fill, merge_sz, a->count + b->count)))
+        return 0;
+    return 1;
+}
+
+#define quicklistNodeUpdateSz(node)                                            \
+    do {                                                                       \
+        (node)->sz = lpBytes((node)->entry);                                   \
+    } while (0)
+
+static quicklistNode* __quicklistCreatePlainNode(void *value, size_t sz) {
+    quicklistNode *new_node = quicklistCreateNode();
+    new_node->entry = zmalloc(sz);
+    new_node->container = QUICKLIST_NODE_CONTAINER_PLAIN;
+    memcpy(new_node->entry, value, sz);
+    new_node->sz = sz;
+    new_node->count++;
+    return new_node;
+}
+
+static void __quicklistInsertPlainNode(quicklist *quicklist, quicklistNode *old_node,
+                                       void *value, size_t sz, int after) {
+    __quicklistInsertNode(quicklist, old_node, __quicklistCreatePlainNode(value, sz), after);
+    quicklist->count++;
+}
+
+/* Add new entry to head node of quicklist.
+ *
+ * Returns 0 if used existing head.
+ * Returns 1 if new head created. */
+int quicklistPushHead(quicklist *quicklist, void *value, size_t sz) {
+    quicklistNode *orig_head = quicklist->head;
+
+    if (unlikely(isLargeElement(sz))) {
+        __quicklistInsertPlainNode(quicklist, quicklist->head, value, sz, 0);
+        return 1;
+    }
+
+    if (likely(
+            _quicklistNodeAllowInsert(quicklist->head, quicklist->fill, sz))) {
+        quicklist->head->entry = lpPrepend(quicklist->head->entry, value, sz);
+        quicklistNodeUpdateSz(quicklist->head);
+    } else {
+        quicklistNode *node = quicklistCreateNode();
+        node->entry = lpPrepend(lpNew(0), value, sz);
+
+        quicklistNodeUpdateSz(node);
+        _quicklistInsertNodeBefore(quicklist, quicklist->head, node);
+    }
+    quicklist->count++;
+    quicklist->head->count++;
+    return (orig_head != quicklist->head);
+}
+
+/* Add new entry to tail node of quicklist.
+ *
+ * Returns 0 if used existing tail.
+ * Returns 1 if new tail created. */
+int quicklistPushTail(quicklist *quicklist, void *value, size_t sz) {
+    quicklistNode *orig_tail = quicklist->tail;
+    if (unlikely(isLargeElement(sz))) {
+        __quicklistInsertPlainNode(quicklist, quicklist->tail, value, sz, 1);
+        return 1;
+    }
+
+    if (likely(
+            _quicklistNodeAllowInsert(quicklist->tail, quicklist->fill, sz))) {
+        quicklist->tail->entry = lpAppend(quicklist->tail->entry, value, sz);
+        quicklistNodeUpdateSz(quicklist->tail);
+    } else {
+        quicklistNode *node = quicklistCreateNode();
+        node->entry = lpAppend(lpNew(0), value, sz);
+
+        quicklistNodeUpdateSz(node);
+        _quicklistInsertNodeAfter(quicklist, quicklist->tail, node);
+    }
+    quicklist->count++;
+    quicklist->tail->count++;
+    return (orig_tail != quicklist->tail);
+}
+
+/* Create new node consisting of a pre-formed listpack.
+ * Used for loading RDBs where entire listpacks have been stored
+ * to be retrieved later. */
+void quicklistAppendListpack(quicklist *quicklist, unsigned char *zl) {
+    quicklistNode *node = quicklistCreateNode();
+
+    node->entry = zl;
+    node->count = lpLength(node->entry);
+    node->sz = lpBytes(zl);
+
+    _quicklistInsertNodeAfter(quicklist, quicklist->tail, node);
+    quicklist->count += node->count;
+}
+
+/* Create new node consisting of a pre-formed plain node.
+ * Used for loading RDBs where entire plain node has been stored
+ * to be retrieved later.
+ * data - the data to add (pointer becomes the responsibility of quicklist) */
+void quicklistAppendPlainNode(quicklist *quicklist, unsigned char *data, size_t sz) {
+    quicklistNode *node = quicklistCreateNode();
+
+    node->entry = data;
+    node->count = 1;
+    node->sz = sz;
+    node->container = QUICKLIST_NODE_CONTAINER_PLAIN;
+
+    _quicklistInsertNodeAfter(quicklist, quicklist->tail, node);
+    quicklist->count += node->count;
+}
+
+#define quicklistDeleteIfEmpty(ql, n)                                          \
+    do {                                                                       \
+        if ((n)->count == 0) {                                                 \
+            __quicklistDelNode((ql), (n));                                     \
+            (n) = NULL;                                                        \
+        }                                                                      \
+    } while (0)
+
+REDIS_STATIC void __quicklistDelNode(quicklist *quicklist,
+                                     quicklistNode *node) {
+    /* Update the bookmark if any */
+    quicklistBookmark *bm = _quicklistBookmarkFindByNode(quicklist, node);
+    if (bm) {
+        bm->node = node->next;
+        /* if the bookmark was to the last node, delete it. */
+        if (!bm->node)
+            _quicklistBookmarkDelete(quicklist, bm);
+    }
+
+    if (node->next)
+        node->next->prev = node->prev;
+    if (node->prev)
+        node->prev->next = node->next;
+
+    if (node == quicklist->tail) {
+        quicklist->tail = node->prev;
+    }
+
+    if (node == quicklist->head) {
+        quicklist->head = node->next;
+    }
+
+    /* Update len first, so in __quicklistCompress we know exactly len */
+    quicklist->len--;
+    quicklist->count -= node->count;
+
+    /* If we deleted a node within our compress depth, we
+     * now have compressed nodes needing to be decompressed. */
+    __quicklistCompress(quicklist, NULL);
+
+    zfree(node->entry);
+    zfree(node);
+}
+
+/* Delete one entry from list given the node for the entry and a pointer
+ * to the entry in the node.
+ *
+ * Note: quicklistDelIndex() *requires* uncompressed nodes because you
+ *       already had to get *p from an uncompressed node somewhere.
+ *
+ * Returns 1 if the entire node was deleted, 0 if node still exists.
+ * Also updates in/out param 'p' with the next offset in the listpack. */
+REDIS_STATIC int quicklistDelIndex(quicklist *quicklist, quicklistNode *node,
+                                   unsigned char **p) {
+    int gone = 0;
+
+    if (unlikely(QL_NODE_IS_PLAIN(node))) {
+        __quicklistDelNode(quicklist, node);
+        return 1;
+    }
+    node->entry = lpDelete(node->entry, *p, p);
+    node->count--;
+    if (node->count == 0) {
+        gone = 1;
+        __quicklistDelNode(quicklist, node);
+    } else {
+        quicklistNodeUpdateSz(node);
+    }
+    quicklist->count--;
+    /* If we deleted the node, the original node is no longer valid */
+    return gone ? 1 : 0;
+}
+
+/* Delete one element represented by 'entry'
+ *
+ * 'entry' stores enough metadata to delete the proper position in
+ * the correct listpack in the correct quicklist node. */
+void quicklistDelEntry(quicklistIter *iter, quicklistEntry *entry) {
+    quicklistNode *prev = entry->node->prev;
+    quicklistNode *next = entry->node->next;
+    int deleted_node = quicklistDelIndex((quicklist *)entry->quicklist,
+                                         entry->node, &entry->zi);
+
+    /* after delete, the zi is now invalid for any future usage. */
+    iter->zi = NULL;
+
+    /* If current node is deleted, we must update iterator node and offset. */
+    if (deleted_node) {
+        if (iter->direction == AL_START_HEAD) {
+            iter->current = next;
+            iter->offset = 0;
+        } else if (iter->direction == AL_START_TAIL) {
+            iter->current = prev;
+            iter->offset = -1;
+        }
+    }
+    /* else if (!deleted_node), no changes needed.
+     * we already reset iter->zi above, and the existing iter->offset
+     * doesn't move again because:
+     *   - [1, 2, 3] => delete offset 1 => [1, 3]: next element still offset 1
+     *   - [1, 2, 3] => delete offset 0 => [2, 3]: next element still offset 0
+     *  if we deleted the last element at offset N and now
+     *  length of this listpack is N-1, the next call into
+     *  quicklistNext() will jump to the next node. */
+}
+
+/* Replace quicklist entry by 'data' with length 'sz'. */
+void quicklistReplaceEntry(quicklistIter *iter, quicklistEntry *entry,
+                           void *data, size_t sz)
+{
+    quicklist* quicklist = iter->quicklist;
+
+    if (likely(!QL_NODE_IS_PLAIN(entry->node) && !isLargeElement(sz))) {
+        entry->node->entry = lpReplace(entry->node->entry, &entry->zi, data, sz);
+        quicklistNodeUpdateSz(entry->node);
+        /* quicklistNext() and quicklistGetIteratorEntryAtIdx() provide an uncompressed node */
+        quicklistCompress(quicklist, entry->node);
+    } else if (QL_NODE_IS_PLAIN(entry->node)) {
+        if (isLargeElement(sz)) {
+            zfree(entry->node->entry);
+            entry->node->entry = zmalloc(sz);
+            entry->node->sz = sz;
+            memcpy(entry->node->entry, data, sz);
+            quicklistCompress(quicklist, entry->node);
+        } else {
+            quicklistInsertAfter(iter, entry, data, sz);
+            __quicklistDelNode(quicklist, entry->node);
+        }
+    } else {
+        entry->node->dont_compress = 1; /* Prevent compression in quicklistInsertAfter() */
+        quicklistInsertAfter(iter, entry, data, sz);
+        if (entry->node->count == 1) {
+            __quicklistDelNode(quicklist, entry->node);
+        } else {
+            unsigned char *p = lpSeek(entry->node->entry, -1);
+            quicklistDelIndex(quicklist, entry->node, &p);
+            entry->node->dont_compress = 0; /* Re-enable compression */
+            quicklistCompress(quicklist, entry->node);
+            quicklistCompress(quicklist, entry->node->next);
+        }
+    }
+
+    /* In any case, we reset iterator to forbid use of iterator after insert.
+     * Notice: iter->current has been compressed above. */
+    resetIterator(iter);
+}
+
+/* Replace quicklist entry at offset 'index' by 'data' with length 'sz'.
+ *
+ * Returns 1 if replace happened.
+ * Returns 0 if replace failed and no changes happened. */
+int quicklistReplaceAtIndex(quicklist *quicklist, long index, void *data,
+                            size_t sz) {
+    quicklistEntry entry;
+    quicklistIter *iter = quicklistGetIteratorEntryAtIdx(quicklist, index, &entry);
+    if (likely(iter)) {
+        quicklistReplaceEntry(iter, &entry, data, sz);
+        quicklistReleaseIterator(iter);
+        return 1;
+    } else {
+        return 0;
+    }
+}
+
+/* Given two nodes, try to merge their listpacks.
+ *
+ * This helps us not have a quicklist with 3 element listpacks if
+ * our fill factor can handle much higher levels.
+ *
+ * Note: 'a' must be to the LEFT of 'b'.
+ *
+ * After calling this function, both 'a' and 'b' should be considered
+ * unusable.  The return value from this function must be used
+ * instead of re-using any of the quicklistNode input arguments.
+ *
+ * Returns the input node picked to merge against or NULL if
+ * merging was not possible. */
+REDIS_STATIC quicklistNode *_quicklistListpackMerge(quicklist *quicklist,
+                                                    quicklistNode *a,
+                                                    quicklistNode *b) {
+    D("Requested merge (a,b) (%u, %u)", a->count, b->count);
+
+    quicklistDecompressNode(a);
+    quicklistDecompressNode(b);
+    if ((lpMerge(&a->entry, &b->entry))) {
+        /* We merged listpacks! Now remove the unused quicklistNode. */
+        quicklistNode *keep = NULL, *nokeep = NULL;
+        if (!a->entry) {
+            nokeep = a;
+            keep = b;
+        } else if (!b->entry) {
+            nokeep = b;
+            keep = a;
+        }
+        keep->count = lpLength(keep->entry);
+        quicklistNodeUpdateSz(keep);
+
+        nokeep->count = 0;
+        __quicklistDelNode(quicklist, nokeep);
+        quicklistCompress(quicklist, keep);
+        return keep;
+    } else {
+        /* else, the merge returned NULL and nothing changed. */
+        return NULL;
+    }
+}
+
+/* Attempt to merge listpacks within two nodes on either side of 'center'.
+ *
+ * We attempt to merge:
+ *   - (center->prev->prev, center->prev)
+ *   - (center->next, center->next->next)
+ *   - (center->prev, center)
+ *   - (center, center->next)
+ */
+REDIS_STATIC void _quicklistMergeNodes(quicklist *quicklist,
+                                       quicklistNode *center) {
+    int fill = quicklist->fill;
+    quicklistNode *prev, *prev_prev, *next, *next_next, *target;
+    prev = prev_prev = next = next_next = target = NULL;
+
+    if (center->prev) {
+        prev = center->prev;
+        if (center->prev->prev)
+            prev_prev = center->prev->prev;
+    }
+
+    if (center->next) {
+        next = center->next;
+        if (center->next->next)
+            next_next = center->next->next;
+    }
+
+    /* Try to merge prev_prev and prev */
+    if (_quicklistNodeAllowMerge(prev, prev_prev, fill)) {
+        _quicklistListpackMerge(quicklist, prev_prev, prev);
+        prev_prev = prev = NULL; /* they could have moved, invalidate them. */
+    }
+
+    /* Try to merge next and next_next */
+    if (_quicklistNodeAllowMerge(next, next_next, fill)) {
+        _quicklistListpackMerge(quicklist, next, next_next);
+        next = next_next = NULL; /* they could have moved, invalidate them. */
+    }
+
+    /* Try to merge center node and previous node */
+    if (_quicklistNodeAllowMerge(center, center->prev, fill)) {
+        target = _quicklistListpackMerge(quicklist, center->prev, center);
+        center = NULL; /* center could have been deleted, invalidate it. */
+    } else {
+        /* else, we didn't merge here, but target needs to be valid below. */
+        target = center;
+    }
+
+    /* Use result of center merge (or original) to merge with next node. */
+    if (_quicklistNodeAllowMerge(target, target->next, fill)) {
+        _quicklistListpackMerge(quicklist, target, target->next);
+    }
+}
+
+/* Split 'node' into two parts, parameterized by 'offset' and 'after'.
+ *
+ * The 'after' argument controls which quicklistNode gets returned.
+ * If 'after'==1, returned node has elements after 'offset'.
+ *                input node keeps elements up to 'offset', including 'offset'.
+ * If 'after'==0, returned node has elements up to 'offset'.
+ *                input node keeps elements after 'offset', including 'offset'.
+ *
+ * Or in other words:
+ * If 'after'==1, returned node will have elements after 'offset'.
+ *                The returned node will have elements [OFFSET+1, END].
+ *                The input node keeps elements [0, OFFSET].
+ * If 'after'==0, returned node will keep elements up to but not including 'offset'.
+ *                The returned node will have elements [0, OFFSET-1].
+ *                The input node keeps elements [OFFSET, END].
+ *
+ * The input node keeps all elements not taken by the returned node.
+ *
+ * Returns newly created node or NULL if split not possible. */
+REDIS_STATIC quicklistNode *_quicklistSplitNode(quicklistNode *node, int offset,
+                                                int after) {
+    size_t zl_sz = node->sz;
+
+    quicklistNode *new_node = quicklistCreateNode();
+    new_node->entry = zmalloc(zl_sz);
+
+    /* Copy original listpack so we can split it */
+    memcpy(new_node->entry, node->entry, zl_sz);
+
+    /* Need positive offset for calculating extent below. */
+    if (offset < 0) offset = node->count + offset;
+
+    /* Ranges to be trimmed: -1 here means "continue deleting until the list ends" */
+    int orig_start = after ? offset + 1 : 0;
+    int orig_extent = after ? -1 : offset;
+    int new_start = after ? 0 : offset;
+    int new_extent = after ? offset + 1 : -1;
+
+    D("After %d (%d); ranges: [%d, %d], [%d, %d]", after, offset, orig_start,
+      orig_extent, new_start, new_extent);
+
+    node->entry = lpDeleteRange(node->entry, orig_start, orig_extent);
+    node->count = lpLength(node->entry);
+    quicklistNodeUpdateSz(node);
+
+    new_node->entry = lpDeleteRange(new_node->entry, new_start, new_extent);
+    new_node->count = lpLength(new_node->entry);
+    quicklistNodeUpdateSz(new_node);
+
+    D("After split lengths: orig (%d), new (%d)", node->count, new_node->count);
+    return new_node;
+}
+
+/* Insert a new entry before or after existing entry 'entry'.
+ *
+ * If after==1, the new value is inserted after 'entry', otherwise
+ * the new value is inserted before 'entry'. */
+REDIS_STATIC void _quicklistInsert(quicklistIter *iter, quicklistEntry *entry,
+                                   void *value, const size_t sz, int after)
+{
+    quicklist *quicklist = iter->quicklist;
+    int full = 0, at_tail = 0, at_head = 0, avail_next = 0, avail_prev = 0;
+    int fill = quicklist->fill;
+    quicklistNode *node = entry->node;
+    quicklistNode *new_node = NULL;
+
+    if (!node) {
+        /* we have no reference node, so let's create only node in the list */
+        D("No node given!");
+        if (unlikely(isLargeElement(sz))) {
+            __quicklistInsertPlainNode(quicklist, quicklist->tail, value, sz, after);
+            return;
+        }
+        new_node = quicklistCreateNode();
+        new_node->entry = lpPrepend(lpNew(0), value, sz);
+        __quicklistInsertNode(quicklist, NULL, new_node, after);
+        new_node->count++;
+        quicklist->count++;
+        return;
+    }
+
+    /* Populate accounting flags for easier boolean checks later */
+    if (!_quicklistNodeAllowInsert(node, fill, sz)) {
+        D("Current node is full with count %d with requested fill %d",
+          node->count, fill);
+        full = 1;
+    }
+
+    if (after && (entry->offset == node->count - 1 || entry->offset == -1)) {
+        D("At Tail of current listpack");
+        at_tail = 1;
+        if (_quicklistNodeAllowInsert(node->next, fill, sz)) {
+            D("Next node is available.");
+            avail_next = 1;
+        }
+    }
+
+    if (!after && (entry->offset == 0 || entry->offset == -(node->count))) {
+        D("At Head");
+        at_head = 1;
+        if (_quicklistNodeAllowInsert(node->prev, fill, sz)) {
+            D("Prev node is available.");
+            avail_prev = 1;
+        }
+    }
+
+    if (unlikely(isLargeElement(sz))) {
+        if (QL_NODE_IS_PLAIN(node) || (at_tail && after) || (at_head && !after)) {
+            __quicklistInsertPlainNode(quicklist, node, value, sz, after);
+        } else {
+            quicklistDecompressNodeForUse(node);
+            new_node = _quicklistSplitNode(node, entry->offset, after);
+            quicklistNode *entry_node = __quicklistCreatePlainNode(value, sz);
+            __quicklistInsertNode(quicklist, node, entry_node, after);
+            __quicklistInsertNode(quicklist, entry_node, new_node, after);
+            quicklist->count++;
+        }
+        return;
+    }
+
+    /* Now determine where and how to insert the new element */
+    if (!full && after) {
+        D("Not full, inserting after current position.");
+        quicklistDecompressNodeForUse(node);
+        node->entry = lpInsertString(node->entry, value, sz, entry->zi, LP_AFTER, NULL);
+        node->count++;
+        quicklistNodeUpdateSz(node);
+        quicklistRecompressOnly(node);
+    } else if (!full && !after) {
+        D("Not full, inserting before current position.");
+        quicklistDecompressNodeForUse(node);
+        node->entry = lpInsertString(node->entry, value, sz, entry->zi, LP_BEFORE, NULL);
+        node->count++;
+        quicklistNodeUpdateSz(node);
+        quicklistRecompressOnly(node);
+    } else if (full && at_tail && avail_next && after) {
+        /* If we are: at tail, next has free space, and inserting after:
+         *   - insert entry at head of next node. */
+        D("Full and tail, but next isn't full; inserting next node head");
+        new_node = node->next;
+        quicklistDecompressNodeForUse(new_node);
+        new_node->entry = lpPrepend(new_node->entry, value, sz);
+        new_node->count++;
+        quicklistNodeUpdateSz(new_node);
+        quicklistRecompressOnly(new_node);
+        quicklistRecompressOnly(node);
+    } else if (full && at_head && avail_prev && !after) {
+        /* If we are: at head, previous has free space, and inserting before:
+         *   - insert entry at tail of previous node. */
+        D("Full and head, but prev isn't full, inserting prev node tail");
+        new_node = node->prev;
+        quicklistDecompressNodeForUse(new_node);
+        new_node->entry = lpAppend(new_node->entry, value, sz);
+        new_node->count++;
+        quicklistNodeUpdateSz(new_node);
+        quicklistRecompressOnly(new_node);
+        quicklistRecompressOnly(node);
+    } else if (full && ((at_tail && !avail_next && after) ||
+                        (at_head && !avail_prev && !after))) {
+        /* If we are: full, and our prev/next has no available space, then:
+         *   - create new node and attach to quicklist */
+        D("\tprovisioning new node...");
+        new_node = quicklistCreateNode();
+        new_node->entry = lpPrepend(lpNew(0), value, sz);
+        new_node->count++;
+        quicklistNodeUpdateSz(new_node);
+        __quicklistInsertNode(quicklist, node, new_node, after);
+    } else if (full) {
+        /* else, node is full we need to split it. */
+        /* covers both after and !after cases */
+        D("\tsplitting node...");
+        quicklistDecompressNodeForUse(node);
+        new_node = _quicklistSplitNode(node, entry->offset, after);
+        if (after)
+            new_node->entry = lpPrepend(new_node->entry, value, sz);
+        else
+            new_node->entry = lpAppend(new_node->entry, value, sz);
+        new_node->count++;
+        quicklistNodeUpdateSz(new_node);
+        __quicklistInsertNode(quicklist, node, new_node, after);
+        _quicklistMergeNodes(quicklist, node);
+    }
+
+    quicklist->count++;
+
+    /* In any case, we reset iterator to forbid use of iterator after insert.
+     * Notice: iter->current has been compressed in _quicklistInsert(). */
+    resetIterator(iter); 
+}
+
+void quicklistInsertBefore(quicklistIter *iter, quicklistEntry *entry,
+                           void *value, const size_t sz)
+{
+    _quicklistInsert(iter, entry, value, sz, 0);
+}
+
+void quicklistInsertAfter(quicklistIter *iter, quicklistEntry *entry,
+                          void *value, const size_t sz)
+{
+    _quicklistInsert(iter, entry, value, sz, 1);
+}
+
+/* Delete a range of elements from the quicklist.
+ *
+ * elements may span across multiple quicklistNodes, so we
+ * have to be careful about tracking where we start and end.
+ *
+ * Returns 1 if entries were deleted, 0 if nothing was deleted. */
+int quicklistDelRange(quicklist *quicklist, const long start,
+                      const long count) {
+    if (count <= 0)
+        return 0;
+
+    unsigned long extent = count; /* range is inclusive of start position */
+
+    if (start >= 0 && extent > (quicklist->count - start)) {
+        /* if requesting delete more elements than exist, limit to list size. */
+        extent = quicklist->count - start;
+    } else if (start < 0 && extent > (unsigned long)(-start)) {
+        /* else, if at negative offset, limit max size to rest of list. */
+        extent = -start; /* c.f. LREM -29 29; just delete until end. */
+    }
+
+    quicklistIter *iter = quicklistGetIteratorAtIdx(quicklist, AL_START_TAIL, start);
+    if (!iter)
+        return 0;
+
+    D("Quicklist delete request for start %ld, count %ld, extent: %ld", start,
+      count, extent);
+    quicklistNode *node = iter->current;
+    long offset = iter->offset;
+    quicklistReleaseIterator(iter);
+
+    /* iterate over next nodes until everything is deleted. */
+    while (extent) {
+        quicklistNode *next = node->next;
+
+        unsigned long del;
+        int delete_entire_node = 0;
+        if (offset == 0 && extent >= node->count) {
+            /* If we are deleting more than the count of this node, we
+             * can just delete the entire node without listpack math. */
+            delete_entire_node = 1;
+            del = node->count;
+        } else if (offset >= 0 && extent + offset >= node->count) {
+            /* If deleting more nodes after this one, calculate delete based
+             * on size of current node. */
+            del = node->count - offset;
+        } else if (offset < 0) {
+            /* If offset is negative, we are in the first run of this loop
+             * and we are deleting the entire range
+             * from this start offset to end of list.  Since the Negative
+             * offset is the number of elements until the tail of the list,
+             * just use it directly as the deletion count. */
+            del = -offset;
+
+            /* If the positive offset is greater than the remaining extent,
+             * we only delete the remaining extent, not the entire offset.
+             */
+            if (del > extent)
+                del = extent;
+        } else {
+            /* else, we are deleting less than the extent of this node, so
+             * use extent directly. */
+            del = extent;
+        }
+
+        D("[%ld]: asking to del: %ld because offset: %d; (ENTIRE NODE: %d), "
+          "node count: %u",
+          extent, del, offset, delete_entire_node, node->count);
+
+        if (delete_entire_node || QL_NODE_IS_PLAIN(node)) {
+            __quicklistDelNode(quicklist, node);
+        } else {
+            quicklistDecompressNodeForUse(node);
+            node->entry = lpDeleteRange(node->entry, offset, del);
+            quicklistNodeUpdateSz(node);
+            node->count -= del;
+            quicklist->count -= del;
+            quicklistDeleteIfEmpty(quicklist, node);
+            if (node)
+                quicklistRecompressOnly(node);
+        }
+
+        extent -= del;
+
+        node = next;
+
+        offset = 0;
+    }
+    return 1;
+}
+
+/* compare between a two entries */
+int quicklistCompare(quicklistEntry* entry, unsigned char *p2, const size_t p2_len) {
+    if (unlikely(QL_NODE_IS_PLAIN(entry->node))) {
+        return ((entry->sz == p2_len) && (memcmp(entry->value, p2, p2_len) == 0));
+    }
+    return lpCompare(entry->zi, p2, p2_len);
+}
+
+/* Returns a quicklist iterator 'iter'. After the initialization every
+ * call to quicklistNext() will return the next element of the quicklist. */
+quicklistIter *quicklistGetIterator(quicklist *quicklist, int direction) {
+    quicklistIter *iter;
+
+    iter = zmalloc(sizeof(*iter));
+
+    if (direction == AL_START_HEAD) {
+        iter->current = quicklist->head;
+        iter->offset = 0;
+    } else if (direction == AL_START_TAIL) {
+        iter->current = quicklist->tail;
+        iter->offset = -1;
+    }
+
+    iter->direction = direction;
+    iter->quicklist = quicklist;
+
+    iter->zi = NULL;
+
+    return iter;
+}
+
+/* Initialize an iterator at a specific offset 'idx' and make the iterator
+ * return nodes in 'direction' direction. */
+quicklistIter *quicklistGetIteratorAtIdx(quicklist *quicklist,
+                                         const int direction,
+                                         const long long idx)
+{
+    quicklistNode *n;
+    unsigned long long accum = 0;
+    unsigned long long index;
+    int forward = idx < 0 ? 0 : 1; /* < 0 -> reverse, 0+ -> forward */
+
+    index = forward ? idx : (-idx) - 1;
+    if (index >= quicklist->count)
+        return NULL;
+
+    /* Seek in the other direction if that way is shorter. */
+    int seek_forward = forward;
+    unsigned long long seek_index = index;
+    if (index > (quicklist->count - 1) / 2) {
+        seek_forward = !forward;
+        seek_index = quicklist->count - 1 - index;
+    }
+
+    n = seek_forward ? quicklist->head : quicklist->tail;
+    while (likely(n)) {
+        if ((accum + n->count) > seek_index) {
+            break;
+        } else {
+            D("Skipping over (%p) %u at accum %lld", (void *)n, n->count,
+              accum);
+            accum += n->count;
+            n = seek_forward ? n->next : n->prev;
+        }
+    }
+
+    if (!n)
+        return NULL;
+
+    /* Fix accum so it looks like we seeked in the other direction. */
+    if (seek_forward != forward) accum = quicklist->count - n->count - accum;
+
+    D("Found node: %p at accum %llu, idx %llu, sub+ %llu, sub- %llu", (void *)n,
+      accum, index, index - accum, (-index) - 1 + accum);
+
+    quicklistIter *iter = quicklistGetIterator(quicklist, direction);
+    iter->current = n;
+    if (forward) {
+        /* forward = normal head-to-tail offset. */
+        iter->offset = index - accum;
+    } else {
+        /* reverse = need negative offset for tail-to-head, so undo
+         * the result of the original index = (-idx) - 1 above. */
+        iter->offset = (-index) - 1 + accum;
+    }
+
+    return iter;
+}
+
+/* Release iterator.
+ * If we still have a valid current node, then re-encode current node. */
+void quicklistReleaseIterator(quicklistIter *iter) {
+    if (!iter) return;
+    if (iter->current)
+        quicklistCompress(iter->quicklist, iter->current);
+
+    zfree(iter);
+}
+
+/* Get next element in iterator.
+ *
+ * Note: You must NOT insert into the list while iterating over it.
+ * You *may* delete from the list while iterating using the
+ * quicklistDelEntry() function.
+ * If you insert into the quicklist while iterating, you should
+ * re-create the iterator after your addition.
+ *
+ * iter = quicklistGetIterator(quicklist,<direction>);
+ * quicklistEntry entry;
+ * while (quicklistNext(iter, &entry)) {
+ *     if (entry.value)
+ *          [[ use entry.value with entry.sz ]]
+ *     else
+ *          [[ use entry.longval ]]
+ * }
+ *
+ * Populates 'entry' with values for this iteration.
+ * Returns 0 when iteration is complete or if iteration not possible.
+ * If return value is 0, the contents of 'entry' are not valid.
+ */
+int quicklistNext(quicklistIter *iter, quicklistEntry *entry) {
+    initEntry(entry);
+
+    if (!iter) {
+        D("Returning because no iter!");
+        return 0;
+    }
+
+    entry->quicklist = iter->quicklist;
+    entry->node = iter->current;
+
+    if (!iter->current) {
+        D("Returning because current node is NULL");
+        return 0;
+    }
+
+    unsigned char *(*nextFn)(unsigned char *, unsigned char *) = NULL;
+    int offset_update = 0;
+
+    int plain = QL_NODE_IS_PLAIN(iter->current);
+    if (!iter->zi) {
+        /* If !zi, use current index. */
+        quicklistDecompressNodeForUse(iter->current);
+        if (unlikely(plain))
+            iter->zi = iter->current->entry;
+        else
+            iter->zi = lpSeek(iter->current->entry, iter->offset);
+    } else if (unlikely(plain)) {
+        iter->zi = NULL;
+    } else {
+        /* else, use existing iterator offset and get prev/next as necessary. */
+        if (iter->direction == AL_START_HEAD) {
+            nextFn = lpNext;
+            offset_update = 1;
+        } else if (iter->direction == AL_START_TAIL) {
+            nextFn = lpPrev;
+            offset_update = -1;
+        }
+        iter->zi = nextFn(iter->current->entry, iter->zi);
+        iter->offset += offset_update;
+    }
+
+    entry->zi = iter->zi;
+    entry->offset = iter->offset;
+
+    if (iter->zi) {
+        if (unlikely(plain)) {
+            entry->value = entry->node->entry;
+            entry->sz = entry->node->sz;
+            return 1;
+        }
+        /* Populate value from existing listpack position */
+        unsigned int sz = 0;
+        entry->value = lpGetValue(entry->zi, &sz, &entry->longval);
+        entry->sz = sz;
+        return 1;
+    } else {
+        /* We ran out of listpack entries.
+         * Pick next node, update offset, then re-run retrieval. */
+        quicklistCompress(iter->quicklist, iter->current);
+        if (iter->direction == AL_START_HEAD) {
+            /* Forward traversal */
+            D("Jumping to start of next node");
+            iter->current = iter->current->next;
+            iter->offset = 0;
+        } else if (iter->direction == AL_START_TAIL) {
+            /* Reverse traversal */
+            D("Jumping to end of previous node");
+            iter->current = iter->current->prev;
+            iter->offset = -1;
+        }
+        iter->zi = NULL;
+        return quicklistNext(iter, entry);
+    }
+}
+
+/* Sets the direction of a quicklist iterator. */
+void quicklistSetDirection(quicklistIter *iter, int direction) {
+    iter->direction = direction;
+}
+
+/* Duplicate the quicklist.
+ * On success a copy of the original quicklist is returned.
+ *
+ * The original quicklist both on success or error is never modified.
+ *
+ * Returns newly allocated quicklist. */
+quicklist *quicklistDup(quicklist *orig) {
+    quicklist *copy;
+
+    copy = quicklistNew(orig->fill, orig->compress);
+
+    for (quicklistNode *current = orig->head; current;
+         current = current->next) {
+        quicklistNode *node = quicklistCreateNode();
+
+        if (current->encoding == QUICKLIST_NODE_ENCODING_LZF) {
+            quicklistLZF *lzf = (quicklistLZF *)current->entry;
+            size_t lzf_sz = sizeof(*lzf) + lzf->sz;
+            node->entry = zmalloc(lzf_sz);
+            memcpy(node->entry, current->entry, lzf_sz);
+        } else if (current->encoding == QUICKLIST_NODE_ENCODING_RAW) {
+            node->entry = zmalloc(current->sz);
+            memcpy(node->entry, current->entry, current->sz);
+        }
+
+        node->count = current->count;
+        copy->count += node->count;
+        node->sz = current->sz;
+        node->encoding = current->encoding;
+        node->container = current->container;
+
+        _quicklistInsertNodeAfter(copy, copy->tail, node);
+    }
+
+    /* copy->count must equal orig->count here */
+    return copy;
+}
+
+/* Populate 'entry' with the element at the specified zero-based index
+ * where 0 is the head, 1 is the element next to head
+ * and so on. Negative integers are used in order to count
+ * from the tail, -1 is the last element, -2 the penultimate
+ * and so on. If the index is out of range 0 is returned.
+ *
+ * Returns an iterator at a specific offset 'idx' if element found
+ * Returns NULL if element not found */
+quicklistIter *quicklistGetIteratorEntryAtIdx(quicklist *quicklist, const long long idx,
+                                              quicklistEntry *entry)
+{
+    quicklistIter *iter = quicklistGetIteratorAtIdx(quicklist, AL_START_TAIL, idx);
+    if (!iter) return NULL;
+    assert(quicklistNext(iter, entry));
+    return iter;
+}
+
+static void quicklistRotatePlain(quicklist *quicklist) {
+    quicklistNode *new_head = quicklist->tail;
+    quicklistNode *new_tail = quicklist->tail->prev;
+    quicklist->head->prev = new_head;
+    new_tail->next = NULL;
+    new_head->next = quicklist->head;
+    new_head->prev = NULL;
+    quicklist->head = new_head;
+    quicklist->tail = new_tail;
+}
+
+/* Rotate quicklist by moving the tail element to the head. */
+void quicklistRotate(quicklist *quicklist) {
+    if (quicklist->count <= 1)
+        return;
+
+    if (unlikely(QL_NODE_IS_PLAIN(quicklist->tail))) {
+        quicklistRotatePlain(quicklist);
+        return;
+    }
+
+    /* First, get the tail entry */
+    unsigned char *p = lpSeek(quicklist->tail->entry, -1);
+    unsigned char *value, *tmp;
+    long long longval;
+    unsigned int sz;
+    char longstr[32] = {0};
+    tmp = lpGetValue(p, &sz, &longval);
+
+    /* If value found is NULL, then lpGet populated longval instead */
+    if (!tmp) {
+        /* Write the longval as a string so we can re-add it */
+        sz = ll2string(longstr, sizeof(longstr), longval);
+        value = (unsigned char *)longstr;
+    } else if (quicklist->len == 1) {
+        /* Copy buffer since there could be a memory overlap when move
+         * entity from tail to head in the same listpack. */
+        value = zmalloc(sz);
+        memcpy(value, tmp, sz);
+    } else {
+        value = tmp;
+    }
+
+    /* Add tail entry to head (must happen before tail is deleted). */
+    quicklistPushHead(quicklist, value, sz);
+
+    /* If quicklist has only one node, the head listpack is also the
+     * tail listpack and PushHead() could have reallocated our single listpack,
+     * which would make our pre-existing 'p' unusable. */
+    if (quicklist->len == 1) {
+        p = lpSeek(quicklist->tail->entry, -1);
+    }
+
+    /* Remove tail entry. */
+    quicklistDelIndex(quicklist, quicklist->tail, &p);
+    if (value != (unsigned char*)longstr && value != tmp)
+        zfree(value);
+}
+
+/* pop from quicklist and return result in 'data' ptr.  Value of 'data'
+ * is the return value of 'saver' function pointer if the data is NOT a number.
+ *
+ * If the quicklist element is a long long, then the return value is returned in
+ * 'sval'.
+ *
+ * Return value of 0 means no elements available.
+ * Return value of 1 means check 'data' and 'sval' for values.
+ * If 'data' is set, use 'data' and 'sz'.  Otherwise, use 'sval'. */
+int quicklistPopCustom(quicklist *quicklist, int where, unsigned char **data,
+                       size_t *sz, long long *sval,
+                       void *(*saver)(unsigned char *data, size_t sz)) {
+    unsigned char *p;
+    unsigned char *vstr;
+    unsigned int vlen;
+    long long vlong;
+    int pos = (where == QUICKLIST_HEAD) ? 0 : -1;
+
+    if (quicklist->count == 0)
+        return 0;
+
+    if (data)
+        *data = NULL;
+    if (sz)
+        *sz = 0;
+    if (sval)
+        *sval = -123456789;
+
+    quicklistNode *node;
+    if (where == QUICKLIST_HEAD && quicklist->head) {
+        node = quicklist->head;
+    } else if (where == QUICKLIST_TAIL && quicklist->tail) {
+        node = quicklist->tail;
+    } else {
+        return 0;
+    }
+
+    /* The head and tail should never be compressed */
+    assert(node->encoding != QUICKLIST_NODE_ENCODING_LZF);
+
+    if (unlikely(QL_NODE_IS_PLAIN(node))) {
+        if (data)
+            *data = saver(node->entry, node->sz);
+        if (sz)
+            *sz = node->sz;
+        quicklistDelIndex(quicklist, node, NULL);
+        return 1;
+    }
+
+    p = lpSeek(node->entry, pos);
+    vstr = lpGetValue(p, &vlen, &vlong);
+    if (vstr) {
+        if (data)
+            *data = saver(vstr, vlen);
+        if (sz)
+            *sz = vlen;
+    } else {
+        if (data)
+            *data = NULL;
+        if (sval)
+            *sval = vlong;
+    }
+    quicklistDelIndex(quicklist, node, &p);
+    return 1;
+}
+
+/* Return a malloc'd copy of data passed in */
+REDIS_STATIC void *_quicklistSaver(unsigned char *data, size_t sz) {
+    unsigned char *vstr;
+    if (data) {
+        vstr = zmalloc(sz);
+        memcpy(vstr, data, sz);
+        return vstr;
+    }
+    return NULL;
+}
+
+/* Default pop function
+ *
+ * Returns malloc'd value from quicklist */
+int quicklistPop(quicklist *quicklist, int where, unsigned char **data,
+                 size_t *sz, long long *slong) {
+    unsigned char *vstr = NULL;
+    size_t vlen = 0;
+    long long vlong = 0;
+    if (quicklist->count == 0)
+        return 0;
+    int ret = quicklistPopCustom(quicklist, where, &vstr, &vlen, &vlong,
+                                 _quicklistSaver);
+    if (data)
+        *data = vstr;
+    if (slong)
+        *slong = vlong;
+    if (sz)
+        *sz = vlen;
+    return ret;
+}
+
+/* Wrapper to allow argument-based switching between HEAD/TAIL pop */
+void quicklistPush(quicklist *quicklist, void *value, const size_t sz,
+                   int where) {
+    /* The head and tail should never be compressed (we don't attempt to decompress them) */
+    if (quicklist->head)
+        assert(quicklist->head->encoding != QUICKLIST_NODE_ENCODING_LZF);
+    if (quicklist->tail)
+        assert(quicklist->tail->encoding != QUICKLIST_NODE_ENCODING_LZF);
+
+    if (where == QUICKLIST_HEAD) {
+        quicklistPushHead(quicklist, value, sz);
+    } else if (where == QUICKLIST_TAIL) {
+        quicklistPushTail(quicklist, value, sz);
+    }
+}
+
+/* Print info of quicklist which is used in debugCommand. */
+void quicklistRepr(unsigned char *ql, int full) {
+    int i = 0;
+    quicklist *quicklist  = (struct quicklist*) ql;
+    printf("{count : %ld}\n", quicklist->count);
+    printf("{len : %ld}\n", quicklist->len);
+    printf("{fill : %d}\n", quicklist->fill);
+    printf("{compress : %d}\n", quicklist->compress);
+    printf("{bookmark_count : %d}\n", quicklist->bookmark_count);
+    quicklistNode* node = quicklist->head;
+
+    while(node != NULL) {
+        printf("{quicklist node(%d)\n", i++);
+        printf("{container : %s, encoding: %s, size: %zu, count: %d, recompress: %d, attempted_compress: %d}\n",
+               QL_NODE_IS_PLAIN(node) ? "PLAIN": "PACKED",
+               (node->encoding == QUICKLIST_NODE_ENCODING_RAW) ? "RAW": "LZF",
+               node->sz,
+               node->count,
+               node->recompress,
+               node->attempted_compress);
+
+        if (full) {
+            quicklistDecompressNode(node);
+            if (node->container == QUICKLIST_NODE_CONTAINER_PACKED) {
+                printf("{ listpack:\n");
+                lpRepr(node->entry);
+                printf("}\n");
+
+            } else if (QL_NODE_IS_PLAIN(node)) {
+                printf("{ entry : %s }\n", node->entry);
+            }
+            printf("}\n");
+            quicklistRecompressOnly(node);
+        }
+        node = node->next;
+    }
+}
+
+/* Create or update a bookmark in the list which will be updated to the next node
+ * automatically when the one referenced gets deleted.
+ * Returns 1 on success (creation of new bookmark or override of an existing one).
+ * Returns 0 on failure (reached the maximum supported number of bookmarks).
+ * NOTE: use short simple names, so that string compare on find is quick.
+ * NOTE: bookmark creation may re-allocate the quicklist, so the input pointer
+         may change and it's the caller responsibility to update the reference.
+ */
+int quicklistBookmarkCreate(quicklist **ql_ref, const char *name, quicklistNode *node) {
+    quicklist *ql = *ql_ref;
+    if (ql->bookmark_count >= QL_MAX_BM)
+        return 0;
+    quicklistBookmark *bm = _quicklistBookmarkFindByName(ql, name);
+    if (bm) {
+        bm->node = node;
+        return 1;
+    }
+    ql = zrealloc(ql, sizeof(quicklist) + (ql->bookmark_count+1) * sizeof(quicklistBookmark));
+    *ql_ref = ql;
+    ql->bookmarks[ql->bookmark_count].node = node;
+    ql->bookmarks[ql->bookmark_count].name = zstrdup(name);
+    ql->bookmark_count++;
+    return 1;
+}
+
+/* Find the quicklist node referenced by a named bookmark.
+ * When the bookmarked node is deleted the bookmark is updated to the next node,
+ * and if that's the last node, the bookmark is deleted (so find returns NULL). */
+quicklistNode *quicklistBookmarkFind(quicklist *ql, const char *name) {
+    quicklistBookmark *bm = _quicklistBookmarkFindByName(ql, name);
+    if (!bm) return NULL;
+    return bm->node;
+}
+
+/* Delete a named bookmark.
+ * returns 0 if bookmark was not found, and 1 if deleted.
+ * Note that the bookmark memory is not freed yet, and is kept for future use. */
+int quicklistBookmarkDelete(quicklist *ql, const char *name) {
+    quicklistBookmark *bm = _quicklistBookmarkFindByName(ql, name);
+    if (!bm)
+        return 0;
+    _quicklistBookmarkDelete(ql, bm);
+    return 1;
+}
+
+quicklistBookmark *_quicklistBookmarkFindByName(quicklist *ql, const char *name) {
+    unsigned i;
+    for (i=0; i<ql->bookmark_count; i++) {
+        if (!strcmp(ql->bookmarks[i].name, name)) {
+            return &ql->bookmarks[i];
+        }
+    }
+    return NULL;
+}
+
+quicklistBookmark *_quicklistBookmarkFindByNode(quicklist *ql, quicklistNode *node) {
+    unsigned i;
+    for (i=0; i<ql->bookmark_count; i++) {
+        if (ql->bookmarks[i].node == node) {
+            return &ql->bookmarks[i];
+        }
+    }
+    return NULL;
+}
+
+void _quicklistBookmarkDelete(quicklist *ql, quicklistBookmark *bm) {
+    int index = bm - ql->bookmarks;
+    zfree(bm->name);
+    ql->bookmark_count--;
+    memmove(bm, bm+1, (ql->bookmark_count - index)* sizeof(*bm));
+    /* NOTE: We do not shrink (realloc) the quicklist yet (to avoid resonance,
+     * it may be re-used later (a call to realloc may NOP). */
+}
+
+void quicklistBookmarksClear(quicklist *ql) {
+    while (ql->bookmark_count)
+        zfree(ql->bookmarks[--ql->bookmark_count].name);
+    /* NOTE: We do not shrink (realloc) the quick list. main use case for this
+     * function is just before releasing the allocation. */
+}
+
+/* The rest of this file is test cases and test helpers. */
+#ifdef REDIS_TEST
+#include <stdint.h>
+#include <sys/time.h>
+#include "testhelp.h"
+#include <stdlib.h>
+
+#define yell(str, ...) printf("ERROR! " str "\n\n", __VA_ARGS__)
+
+#define ERROR                                                                  \
+    do {                                                                       \
+        printf("\tERROR!\n");                                                  \
+        err++;                                                                 \
+    } while (0)
+
+#define ERR(x, ...)                                                            \
+    do {                                                                       \
+        printf("%s:%s:%d:\t", __FILE__, __func__, __LINE__);                   \
+        printf("ERROR! " x "\n", __VA_ARGS__);                                 \
+        err++;                                                                 \
+    } while (0)
+
+#define TEST(name) printf("test — %s\n", name);
+#define TEST_DESC(name, ...) printf("test — " name "\n", __VA_ARGS__);
+
+#define QL_TEST_VERBOSE 0
+
+#define UNUSED(x) (void)(x)
+static void ql_info(quicklist *ql) {
+#if QL_TEST_VERBOSE
+    printf("Container length: %lu\n", ql->len);
+    printf("Container size: %lu\n", ql->count);
+    if (ql->head)
+        printf("\t(zsize head: %lu)\n", lpLength(ql->head->entry));
+    if (ql->tail)
+        printf("\t(zsize tail: %lu)\n", lpLength(ql->tail->entry));
+    printf("\n");
+#else
+    UNUSED(ql);
+#endif
+}
+
+/* Return the UNIX time in microseconds */
+static long long ustime(void) {
+    struct timeval tv;
+    long long ust;
+
+    gettimeofday(&tv, NULL);
+    ust = ((long long)tv.tv_sec) * 1000000;
+    ust += tv.tv_usec;
+    return ust;
+}
+
+/* Return the UNIX time in milliseconds */
+static long long mstime(void) { return ustime() / 1000; }
+
+/* Iterate over an entire quicklist.
+ * Print the list if 'print' == 1.
+ *
+ * Returns physical count of elements found by iterating over the list. */
+static int _itrprintr(quicklist *ql, int print, int forward) {
+    quicklistIter *iter =
+        quicklistGetIterator(ql, forward ? AL_START_HEAD : AL_START_TAIL);
+    quicklistEntry entry;
+    int i = 0;
+    int p = 0;
+    quicklistNode *prev = NULL;
+    while (quicklistNext(iter, &entry)) {
+        if (entry.node != prev) {
+            /* Count the number of list nodes too */
+            p++;
+            prev = entry.node;
+        }
+        if (print) {
+            int size = (entry.sz > (1<<20)) ? 1<<20 : entry.sz;
+            printf("[%3d (%2d)]: [%.*s] (%lld)\n", i, p, size,
+                   (char *)entry.value, entry.longval);
+        }
+        i++;
+    }
+    quicklistReleaseIterator(iter);
+    return i;
+}
+static int itrprintr(quicklist *ql, int print) {
+    return _itrprintr(ql, print, 1);
+}
+
+static int itrprintr_rev(quicklist *ql, int print) {
+    return _itrprintr(ql, print, 0);
+}
+
+#define ql_verify(a, b, c, d, e)                                               \
+    do {                                                                       \
+        err += _ql_verify((a), (b), (c), (d), (e));                            \
+    } while (0)
+
+static int _ql_verify_compress(quicklist *ql) {
+    int errors = 0;
+    if (quicklistAllowsCompression(ql)) {
+        quicklistNode *node = ql->head;
+        unsigned int low_raw = ql->compress;
+        unsigned int high_raw = ql->len - ql->compress;
+
+        for (unsigned int at = 0; at < ql->len; at++, node = node->next) {
+            if (node && (at < low_raw || at >= high_raw)) {
+                if (node->encoding != QUICKLIST_NODE_ENCODING_RAW) {
+                    yell("Incorrect compression: node %d is "
+                         "compressed at depth %d ((%u, %u); total "
+                         "nodes: %lu; size: %zu; recompress: %d)",
+                         at, ql->compress, low_raw, high_raw, ql->len, node->sz,
+                         node->recompress);
+                    errors++;
+                }
+            } else {
+                if (node->encoding != QUICKLIST_NODE_ENCODING_LZF &&
+                    !node->attempted_compress) {
+                    yell("Incorrect non-compression: node %d is NOT "
+                         "compressed at depth %d ((%u, %u); total "
+                         "nodes: %lu; size: %zu; recompress: %d; attempted: %d)",
+                         at, ql->compress, low_raw, high_raw, ql->len, node->sz,
+                         node->recompress, node->attempted_compress);
+                    errors++;
+                }
+            }
+        }
+    }
+    return errors;
+}
+
+/* Verify list metadata matches physical list contents. */
+static int _ql_verify(quicklist *ql, uint32_t len, uint32_t count,
+                      uint32_t head_count, uint32_t tail_count) {
+    int errors = 0;
+
+    ql_info(ql);
+    if (len != ql->len) {
+        yell("quicklist length wrong: expected %d, got %lu", len, ql->len);
+        errors++;
+    }
+
+    if (count != ql->count) {
+        yell("quicklist count wrong: expected %d, got %lu", count, ql->count);
+        errors++;
+    }
+
+    int loopr = itrprintr(ql, 0);
+    if (loopr != (int)ql->count) {
+        yell("quicklist cached count not match actual count: expected %lu, got "
+             "%d",
+             ql->count, loopr);
+        errors++;
+    }
+
+    int rloopr = itrprintr_rev(ql, 0);
+    if (loopr != rloopr) {
+        yell("quicklist has different forward count than reverse count!  "
+             "Forward count is %d, reverse count is %d.",
+             loopr, rloopr);
+        errors++;
+    }
+
+    if (ql->len == 0 && !errors) {
+        return errors;
+    }
+
+    if (ql->head && head_count != ql->head->count &&
+        head_count != lpLength(ql->head->entry)) {
+        yell("quicklist head count wrong: expected %d, "
+             "got cached %d vs. actual %lu",
+             head_count, ql->head->count, lpLength(ql->head->entry));
+        errors++;
+    }
+
+    if (ql->tail && tail_count != ql->tail->count &&
+        tail_count != lpLength(ql->tail->entry)) {
+        yell("quicklist tail count wrong: expected %d, "
+             "got cached %u vs. actual %lu",
+             tail_count, ql->tail->count, lpLength(ql->tail->entry));
+        errors++;
+    }
+
+    errors += _ql_verify_compress(ql);
+    return errors;
+}
+
+/* Release iterator and verify compress correctly. */
+static void ql_release_iterator(quicklistIter *iter) {
+    quicklist *ql = NULL;
+    if (iter) ql = iter->quicklist;
+    quicklistReleaseIterator(iter);
+    if (ql) assert(!_ql_verify_compress(ql));
+}
+
+/* Generate new string concatenating integer i against string 'prefix' */
+static char *genstr(char *prefix, int i) {
+    static char result[64] = {0};
+    snprintf(result, sizeof(result), "%s%d", prefix, i);
+    return result;
+}
+
+static void randstring(unsigned char *target, size_t sz) {
+    size_t p = 0;
+    int minval, maxval;
+    switch(rand() % 3) {
+    case 0:
+        minval = 'a';
+        maxval = 'z';
+    break;
+    case 1:
+        minval = '0';
+        maxval = '9';
+    break;
+    case 2:
+        minval = 'A';
+        maxval = 'Z';
+    break;
+    default:
+        assert(NULL);
+    }
+
+    while(p < sz)
+        target[p++] = minval+rand()%(maxval-minval+1);
+}
+
+/* main test, but callable from other files */
+int quicklistTest(int argc, char *argv[], int flags) {
+    UNUSED(argc);
+    UNUSED(argv);
+
+    int accurate = (flags & REDIS_TEST_ACCURATE);
+    unsigned int err = 0;
+    int optimize_start =
+        -(int)(sizeof(optimization_level) / sizeof(*optimization_level));
+
+    printf("Starting optimization offset at: %d\n", optimize_start);
+
+    int options[] = {0, 1, 2, 3, 4, 5, 6, 10};
+    int fills[] = {-5, -4, -3, -2, -1, 0,
+                   1, 2, 32, 66, 128, 999};
+    size_t option_count = sizeof(options) / sizeof(*options);
+    int fill_count = (int)(sizeof(fills) / sizeof(*fills));
+    long long runtime[option_count];
+
+    for (int _i = 0; _i < (int)option_count; _i++) {
+        printf("Testing Compression option %d\n", options[_i]);
+        long long start = mstime();
+        quicklistIter *iter;
+
+        TEST("create list") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            ql_verify(ql, 0, 0, 0, 0);
+            quicklistRelease(ql);
+        }
+
+        TEST("add to tail of empty list") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistPushTail(ql, "hello", 6);
+            /* 1 for head and 1 for tail because 1 node = head = tail */
+            ql_verify(ql, 1, 1, 1, 1);
+            quicklistRelease(ql);
+        }
+
+        TEST("add to head of empty list") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistPushHead(ql, "hello", 6);
+            /* 1 for head and 1 for tail because 1 node = head = tail */
+            ql_verify(ql, 1, 1, 1, 1);
+            quicklistRelease(ql);
+        }
+
+        TEST_DESC("add to tail 5x at compress %d", options[_i]) {
+            for (int f = 0; f < fill_count; f++) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                for (int i = 0; i < 5; i++)
+                    quicklistPushTail(ql, genstr("hello", i), 32);
+                if (ql->count != 5)
+                    ERROR;
+                if (fills[f] == 32)
+                    ql_verify(ql, 1, 5, 5, 5);
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST_DESC("add to head 5x at compress %d", options[_i]) {
+            for (int f = 0; f < fill_count; f++) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                for (int i = 0; i < 5; i++)
+                    quicklistPushHead(ql, genstr("hello", i), 32);
+                if (ql->count != 5)
+                    ERROR;
+                if (fills[f] == 32)
+                    ql_verify(ql, 1, 5, 5, 5);
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST_DESC("add to tail 500x at compress %d", options[_i]) {
+            for (int f = 0; f < fill_count; f++) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                for (int i = 0; i < 500; i++)
+                    quicklistPushTail(ql, genstr("hello", i), 64);
+                if (ql->count != 500)
+                    ERROR;
+                if (fills[f] == 32)
+                    ql_verify(ql, 16, 500, 32, 20);
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST_DESC("add to head 500x at compress %d", options[_i]) {
+            for (int f = 0; f < fill_count; f++) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                for (int i = 0; i < 500; i++)
+                    quicklistPushHead(ql, genstr("hello", i), 32);
+                if (ql->count != 500)
+                    ERROR;
+                if (fills[f] == 32)
+                    ql_verify(ql, 16, 500, 20, 32);
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST("rotate empty") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistRotate(ql);
+            ql_verify(ql, 0, 0, 0, 0);
+            quicklistRelease(ql);
+        }
+
+        TEST("Comprassion Plain node") {
+            char buf[256];
+            quicklistisSetPackedThreshold(1);
+            quicklist *ql = quicklistNew(-2, 1);
+            for (int i = 0; i < 500; i++) {
+                /* Set to 256 to allow the node to be triggered to compress,
+                 * if it is less than 48(nocompress), the test will be successful. */
+                snprintf(buf, sizeof(buf), "hello%d", i);
+                quicklistPushHead(ql, buf, 256);
+            }
+
+            quicklistIter *iter = quicklistGetIterator(ql, AL_START_TAIL);
+            quicklistEntry entry;
+            int i = 0;
+            while (quicklistNext(iter, &entry)) {
+                snprintf(buf, sizeof(buf), "hello%d", i);
+                if (strcmp((char *)entry.value, buf))
+                    ERR("value [%s] didn't match [%s] at position %d",
+                        entry.value, buf, i);
+                i++;
+            }
+            ql_release_iterator(iter);
+            quicklistRelease(ql);
+        }
+
+        TEST("NEXT plain node")
+        {
+            packed_threshold = 3;
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            char *strings[] = {"hello1", "hello2", "h3", "h4", "hello5"};
+
+            for (int i = 0; i < 5; ++i)
+                quicklistPushHead(ql, strings[i], strlen(strings[i]));
+
+            quicklistEntry entry;
+            quicklistIter *iter = quicklistGetIterator(ql, AL_START_TAIL);
+            int j = 0;
+
+            while(quicklistNext(iter, &entry) != 0) {
+                assert(strncmp(strings[j], (char *)entry.value, strlen(strings[j])) == 0);
+                j++;
+            }
+            ql_release_iterator(iter);
+            quicklistRelease(ql);
+        }
+
+        TEST("rotate plain node ") {
+            unsigned char *data = NULL;
+            size_t sz;
+            long long lv;
+            int i =0;
+            packed_threshold = 5;
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistPushHead(ql, "hello1", 6);
+            quicklistPushHead(ql, "hello4", 6);
+            quicklistPushHead(ql, "hello3", 6);
+            quicklistPushHead(ql, "hello2", 6);
+            quicklistRotate(ql);
+
+            for(i = 1 ; i < 5; i++) {
+                quicklistPop(ql, QUICKLIST_HEAD, &data, &sz, &lv);
+                int temp_char = data[5];
+                zfree(data);
+                assert(temp_char == ('0' + i));
+            }
+
+            ql_verify(ql, 0, 0, 0, 0);
+            quicklistRelease(ql);
+            packed_threshold = (1 << 30);
+        }
+
+        TEST("rotate one val once") {
+            for (int f = 0; f < fill_count; f++) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                quicklistPushHead(ql, "hello", 6);
+                quicklistRotate(ql);
+                /* Ignore compression verify because listpack is
+                 * too small to compress. */
+                ql_verify(ql, 1, 1, 1, 1);
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST_DESC("rotate 500 val 5000 times at compress %d", options[_i]) {
+            for (int f = 0; f < fill_count; f++) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                quicklistPushHead(ql, "900", 3);
+                quicklistPushHead(ql, "7000", 4);
+                quicklistPushHead(ql, "-1200", 5);
+                quicklistPushHead(ql, "42", 2);
+                for (int i = 0; i < 500; i++)
+                    quicklistPushHead(ql, genstr("hello", i), 64);
+                ql_info(ql);
+                for (int i = 0; i < 5000; i++) {
+                    ql_info(ql);
+                    quicklistRotate(ql);
+                }
+                if (fills[f] == 1)
+                    ql_verify(ql, 504, 504, 1, 1);
+                else if (fills[f] == 2)
+                    ql_verify(ql, 252, 504, 2, 2);
+                else if (fills[f] == 32)
+                    ql_verify(ql, 16, 504, 32, 24);
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST("pop empty") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistPop(ql, QUICKLIST_HEAD, NULL, NULL, NULL);
+            ql_verify(ql, 0, 0, 0, 0);
+            quicklistRelease(ql);
+        }
+
+        TEST("pop 1 string from 1") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            char *populate = genstr("hello", 331);
+            quicklistPushHead(ql, populate, 32);
+            unsigned char *data;
+            size_t sz;
+            long long lv;
+            ql_info(ql);
+            assert(quicklistPop(ql, QUICKLIST_HEAD, &data, &sz, &lv));
+            assert(data != NULL);
+            assert(sz == 32);
+            if (strcmp(populate, (char *)data)) {
+                int size = sz;
+                ERR("Pop'd value (%.*s) didn't equal original value (%s)", size,
+                    data, populate);
+            }
+            zfree(data);
+            ql_verify(ql, 0, 0, 0, 0);
+            quicklistRelease(ql);
+        }
+
+        TEST("pop head 1 number from 1") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistPushHead(ql, "55513", 5);
+            unsigned char *data;
+            size_t sz;
+            long long lv;
+            ql_info(ql);
+            assert(quicklistPop(ql, QUICKLIST_HEAD, &data, &sz, &lv));
+            assert(data == NULL);
+            assert(lv == 55513);
+            ql_verify(ql, 0, 0, 0, 0);
+            quicklistRelease(ql);
+        }
+
+        TEST("pop head 500 from 500") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            for (int i = 0; i < 500; i++)
+                quicklistPushHead(ql, genstr("hello", i), 32);
+            ql_info(ql);
+            for (int i = 0; i < 500; i++) {
+                unsigned char *data;
+                size_t sz;
+                long long lv;
+                int ret = quicklistPop(ql, QUICKLIST_HEAD, &data, &sz, &lv);
+                assert(ret == 1);
+                assert(data != NULL);
+                assert(sz == 32);
+                if (strcmp(genstr("hello", 499 - i), (char *)data)) {
+                    int size = sz;
+                    ERR("Pop'd value (%.*s) didn't equal original value (%s)",
+                        size, data, genstr("hello", 499 - i));
+                }
+                zfree(data);
+            }
+            ql_verify(ql, 0, 0, 0, 0);
+            quicklistRelease(ql);
+        }
+
+        TEST("pop head 5000 from 500") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            for (int i = 0; i < 500; i++)
+                quicklistPushHead(ql, genstr("hello", i), 32);
+            for (int i = 0; i < 5000; i++) {
+                unsigned char *data;
+                size_t sz;
+                long long lv;
+                int ret = quicklistPop(ql, QUICKLIST_HEAD, &data, &sz, &lv);
+                if (i < 500) {
+                    assert(ret == 1);
+                    assert(data != NULL);
+                    assert(sz == 32);
+                    if (strcmp(genstr("hello", 499 - i), (char *)data)) {
+                        int size = sz;
+                        ERR("Pop'd value (%.*s) didn't equal original value "
+                            "(%s)",
+                            size, data, genstr("hello", 499 - i));
+                    }
+                    zfree(data);
+                } else {
+                    assert(ret == 0);
+                }
+            }
+            ql_verify(ql, 0, 0, 0, 0);
+            quicklistRelease(ql);
+        }
+
+        TEST("iterate forward over 500 list") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistSetFill(ql, 32);
+            for (int i = 0; i < 500; i++)
+                quicklistPushHead(ql, genstr("hello", i), 32);
+            quicklistIter *iter = quicklistGetIterator(ql, AL_START_HEAD);
+            quicklistEntry entry;
+            int i = 499, count = 0;
+            while (quicklistNext(iter, &entry)) {
+                char *h = genstr("hello", i);
+                if (strcmp((char *)entry.value, h))
+                    ERR("value [%s] didn't match [%s] at position %d",
+                        entry.value, h, i);
+                i--;
+                count++;
+            }
+            if (count != 500)
+                ERR("Didn't iterate over exactly 500 elements (%d)", i);
+            ql_verify(ql, 16, 500, 20, 32);
+            ql_release_iterator(iter);
+            quicklistRelease(ql);
+        }
+
+        TEST("iterate reverse over 500 list") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistSetFill(ql, 32);
+            for (int i = 0; i < 500; i++)
+                quicklistPushHead(ql, genstr("hello", i), 32);
+            quicklistIter *iter = quicklistGetIterator(ql, AL_START_TAIL);
+            quicklistEntry entry;
+            int i = 0;
+            while (quicklistNext(iter, &entry)) {
+                char *h = genstr("hello", i);
+                if (strcmp((char *)entry.value, h))
+                    ERR("value [%s] didn't match [%s] at position %d",
+                        entry.value, h, i);
+                i++;
+            }
+            if (i != 500)
+                ERR("Didn't iterate over exactly 500 elements (%d)", i);
+            ql_verify(ql, 16, 500, 20, 32);
+            ql_release_iterator(iter);
+            quicklistRelease(ql);
+        }
+
+        TEST("insert after 1 element") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistPushHead(ql, "hello", 6);
+            quicklistEntry entry;
+            iter = quicklistGetIteratorEntryAtIdx(ql, 0, &entry);
+            quicklistInsertAfter(iter, &entry, "abc", 4);
+            ql_release_iterator(iter);
+            ql_verify(ql, 1, 2, 2, 2);
+
+            /* verify results */
+            iter = quicklistGetIteratorEntryAtIdx(ql, 0, &entry);
+            int sz = entry.sz;
+            if (strncmp((char *)entry.value, "hello", 5)) {
+                ERR("Value 0 didn't match, instead got: %.*s", sz,
+                    entry.value);
+            }
+            ql_release_iterator(iter);
+
+            iter = quicklistGetIteratorEntryAtIdx(ql, 1, &entry);
+            sz = entry.sz;
+            if (strncmp((char *)entry.value, "abc", 3)) {
+                ERR("Value 1 didn't match, instead got: %.*s", sz,
+                    entry.value);
+            }
+            ql_release_iterator(iter);
+            quicklistRelease(ql);
+        }
+
+        TEST("insert before 1 element") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistPushHead(ql, "hello", 6);
+            quicklistEntry entry;
+            iter = quicklistGetIteratorEntryAtIdx(ql, 0, &entry);
+            quicklistInsertBefore(iter, &entry, "abc", 4);
+            ql_release_iterator(iter);
+            ql_verify(ql, 1, 2, 2, 2);
+
+            /* verify results */
+            iter = quicklistGetIteratorEntryAtIdx(ql, 0, &entry);
+            int sz = entry.sz;
+            if (strncmp((char *)entry.value, "abc", 3)) {
+                ERR("Value 0 didn't match, instead got: %.*s", sz,
+                    entry.value);
+            }
+            ql_release_iterator(iter);
+
+            iter = quicklistGetIteratorEntryAtIdx(ql, 1, &entry);
+            sz = entry.sz;
+            if (strncmp((char *)entry.value, "hello", 5)) {
+                ERR("Value 1 didn't match, instead got: %.*s", sz,
+                    entry.value);
+            }
+            ql_release_iterator(iter);
+            quicklistRelease(ql);
+        }
+
+        TEST("insert head while head node is full") {
+            quicklist *ql = quicklistNew(4, options[_i]);
+            for (int i = 0; i < 10; i++)
+                quicklistPushTail(ql, genstr("hello", i), 6);
+            quicklistSetFill(ql, -1);
+            quicklistEntry entry;
+            iter = quicklistGetIteratorEntryAtIdx(ql, -10, &entry);
+            char buf[4096] = {0};
+            quicklistInsertBefore(iter, &entry, buf, 4096);
+            ql_release_iterator(iter);
+            ql_verify(ql, 4, 11, 1, 2);
+            quicklistRelease(ql);
+        }
+
+        TEST("insert tail while tail node is full") {
+            quicklist *ql = quicklistNew(4, options[_i]);
+            for (int i = 0; i < 10; i++)
+                quicklistPushHead(ql, genstr("hello", i), 6);
+            quicklistSetFill(ql, -1);
+            quicklistEntry entry;
+            iter = quicklistGetIteratorEntryAtIdx(ql, -1, &entry);
+            char buf[4096] = {0};
+            quicklistInsertAfter(iter, &entry, buf, 4096);
+            ql_release_iterator(iter);
+            ql_verify(ql, 4, 11, 2, 1);
+            quicklistRelease(ql);
+        }
+
+        TEST_DESC("insert once in elements while iterating at compress %d",
+                  options[_i]) {
+            for (int f = 0; f < fill_count; f++) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                quicklistPushTail(ql, "abc", 3);
+                quicklistSetFill(ql, 1);
+                quicklistPushTail(ql, "def", 3); /* force to unique node */
+                quicklistSetFill(ql, f);
+                quicklistPushTail(ql, "bob", 3); /* force to reset for +3 */
+                quicklistPushTail(ql, "foo", 3);
+                quicklistPushTail(ql, "zoo", 3);
+
+                itrprintr(ql, 0);
+                /* insert "bar" before "bob" while iterating over list. */
+                quicklistIter *iter = quicklistGetIterator(ql, AL_START_HEAD);
+                quicklistEntry entry;
+                while (quicklistNext(iter, &entry)) {
+                    if (!strncmp((char *)entry.value, "bob", 3)) {
+                        /* Insert as fill = 1 so it spills into new node. */
+                        quicklistInsertBefore(iter, &entry, "bar", 3);
+                        break; /* didn't we fix insert-while-iterating? */
+                    }
+                }
+                ql_release_iterator(iter);
+                itrprintr(ql, 0);
+
+                /* verify results */
+                iter = quicklistGetIteratorEntryAtIdx(ql, 0, &entry);
+                int sz = entry.sz;
+
+                if (strncmp((char *)entry.value, "abc", 3))
+                    ERR("Value 0 didn't match, instead got: %.*s", sz,
+                        entry.value);
+                ql_release_iterator(iter);
+
+                iter = quicklistGetIteratorEntryAtIdx(ql, 1, &entry);
+                if (strncmp((char *)entry.value, "def", 3))
+                    ERR("Value 1 didn't match, instead got: %.*s", sz,
+                        entry.value);
+                ql_release_iterator(iter);
+
+                iter = quicklistGetIteratorEntryAtIdx(ql, 2, &entry);
+                if (strncmp((char *)entry.value, "bar", 3))
+                    ERR("Value 2 didn't match, instead got: %.*s", sz,
+                        entry.value);
+                ql_release_iterator(iter);
+
+                iter = quicklistGetIteratorEntryAtIdx(ql, 3, &entry);
+                if (strncmp((char *)entry.value, "bob", 3))
+                    ERR("Value 3 didn't match, instead got: %.*s", sz,
+                        entry.value);
+                ql_release_iterator(iter);
+
+                iter = quicklistGetIteratorEntryAtIdx(ql, 4, &entry);
+                if (strncmp((char *)entry.value, "foo", 3))
+                    ERR("Value 4 didn't match, instead got: %.*s", sz,
+                        entry.value);
+                ql_release_iterator(iter);
+
+                iter = quicklistGetIteratorEntryAtIdx(ql, 5, &entry);
+                if (strncmp((char *)entry.value, "zoo", 3))
+                    ERR("Value 5 didn't match, instead got: %.*s", sz,
+                        entry.value);
+                ql_release_iterator(iter);
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST_DESC("insert [before] 250 new in middle of 500 elements at compress %d",
+                  options[_i]) {
+            for (int f = 0; f < fill_count; f++) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                for (int i = 0; i < 500; i++)
+                    quicklistPushTail(ql, genstr("hello", i), 32);
+                for (int i = 0; i < 250; i++) {
+                    quicklistEntry entry;
+                    iter = quicklistGetIteratorEntryAtIdx(ql, 250, &entry);
+                    quicklistInsertBefore(iter, &entry, genstr("abc", i), 32);
+                    ql_release_iterator(iter);
+                }
+                if (fills[f] == 32)
+                    ql_verify(ql, 25, 750, 32, 20);
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST_DESC("insert [after] 250 new in middle of 500 elements at compress %d",
+                  options[_i]) {
+            for (int f = 0; f < fill_count; f++) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                for (int i = 0; i < 500; i++)
+                    quicklistPushHead(ql, genstr("hello", i), 32);
+                for (int i = 0; i < 250; i++) {
+                    quicklistEntry entry;
+                    iter = quicklistGetIteratorEntryAtIdx(ql, 250, &entry);
+                    quicklistInsertAfter(iter, &entry, genstr("abc", i), 32);
+                    ql_release_iterator(iter);
+                }
+
+                if (ql->count != 750)
+                    ERR("List size not 750, but rather %ld", ql->count);
+
+                if (fills[f] == 32)
+                    ql_verify(ql, 26, 750, 20, 32);
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST("duplicate empty list") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            ql_verify(ql, 0, 0, 0, 0);
+            quicklist *copy = quicklistDup(ql);
+            ql_verify(copy, 0, 0, 0, 0);
+            quicklistRelease(ql);
+            quicklistRelease(copy);
+        }
+
+        TEST("duplicate list of 1 element") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistPushHead(ql, genstr("hello", 3), 32);
+            ql_verify(ql, 1, 1, 1, 1);
+            quicklist *copy = quicklistDup(ql);
+            ql_verify(copy, 1, 1, 1, 1);
+            quicklistRelease(ql);
+            quicklistRelease(copy);
+        }
+
+        TEST("duplicate list of 500") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistSetFill(ql, 32);
+            for (int i = 0; i < 500; i++)
+                quicklistPushHead(ql, genstr("hello", i), 32);
+            ql_verify(ql, 16, 500, 20, 32);
+
+            quicklist *copy = quicklistDup(ql);
+            ql_verify(copy, 16, 500, 20, 32);
+            quicklistRelease(ql);
+            quicklistRelease(copy);
+        }
+
+        for (int f = 0; f < fill_count; f++) {
+            TEST_DESC("index 1,200 from 500 list at fill %d at compress %d", f,
+                      options[_i]) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                for (int i = 0; i < 500; i++)
+                    quicklistPushTail(ql, genstr("hello", i + 1), 32);
+                quicklistEntry entry;
+                iter = quicklistGetIteratorEntryAtIdx(ql, 1, &entry);
+                if (strcmp((char *)entry.value, "hello2") != 0)
+                    ERR("Value: %s", entry.value);
+                ql_release_iterator(iter);
+
+                iter = quicklistGetIteratorEntryAtIdx(ql, 200, &entry);
+                if (strcmp((char *)entry.value, "hello201") != 0)
+                    ERR("Value: %s", entry.value);
+                ql_release_iterator(iter);
+                quicklistRelease(ql);
+            }
+
+            TEST_DESC("index -1,-2 from 500 list at fill %d at compress %d",
+                      fills[f], options[_i]) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                for (int i = 0; i < 500; i++)
+                    quicklistPushTail(ql, genstr("hello", i + 1), 32);
+                quicklistEntry entry;
+                iter = quicklistGetIteratorEntryAtIdx(ql, -1, &entry);
+                if (strcmp((char *)entry.value, "hello500") != 0)
+                    ERR("Value: %s", entry.value);
+                ql_release_iterator(iter);
+
+                iter = quicklistGetIteratorEntryAtIdx(ql, -2, &entry);
+                if (strcmp((char *)entry.value, "hello499") != 0)
+                    ERR("Value: %s", entry.value);
+                ql_release_iterator(iter);
+                quicklistRelease(ql);
+            }
+
+            TEST_DESC("index -100 from 500 list at fill %d at compress %d",
+                      fills[f], options[_i]) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                for (int i = 0; i < 500; i++)
+                    quicklistPushTail(ql, genstr("hello", i + 1), 32);
+                quicklistEntry entry;
+                iter = quicklistGetIteratorEntryAtIdx(ql, -100, &entry);
+                if (strcmp((char *)entry.value, "hello401") != 0)
+                    ERR("Value: %s", entry.value);
+                ql_release_iterator(iter);
+                quicklistRelease(ql);
+            }
+
+            TEST_DESC("index too big +1 from 50 list at fill %d at compress %d",
+                      fills[f], options[_i]) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                for (int i = 0; i < 50; i++)
+                    quicklistPushTail(ql, genstr("hello", i + 1), 32);
+                quicklistEntry entry;
+                int sz = entry.sz;
+                iter = quicklistGetIteratorEntryAtIdx(ql, 50, &entry);
+                if (iter)
+                    ERR("Index found at 50 with 50 list: %.*s", sz,
+                        entry.value);
+                ql_release_iterator(iter);
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST("delete range empty list") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistDelRange(ql, 5, 20);
+            ql_verify(ql, 0, 0, 0, 0);
+            quicklistRelease(ql);
+        }
+
+        TEST("delete range of entire node in list of one node") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            for (int i = 0; i < 32; i++)
+                quicklistPushHead(ql, genstr("hello", i), 32);
+            ql_verify(ql, 1, 32, 32, 32);
+            quicklistDelRange(ql, 0, 32);
+            ql_verify(ql, 0, 0, 0, 0);
+            quicklistRelease(ql);
+        }
+
+        TEST("delete range of entire node with overflow counts") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            for (int i = 0; i < 32; i++)
+                quicklistPushHead(ql, genstr("hello", i), 32);
+            ql_verify(ql, 1, 32, 32, 32);
+            quicklistDelRange(ql, 0, 128);
+            ql_verify(ql, 0, 0, 0, 0);
+            quicklistRelease(ql);
+        }
+
+        TEST("delete middle 100 of 500 list") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistSetFill(ql, 32);
+            for (int i = 0; i < 500; i++)
+                quicklistPushTail(ql, genstr("hello", i + 1), 32);
+            ql_verify(ql, 16, 500, 32, 20);
+            quicklistDelRange(ql, 200, 100);
+            ql_verify(ql, 14, 400, 32, 20);
+            quicklistRelease(ql);
+        }
+
+        TEST("delete less than fill but across nodes") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistSetFill(ql, 32);
+            for (int i = 0; i < 500; i++)
+                quicklistPushTail(ql, genstr("hello", i + 1), 32);
+            ql_verify(ql, 16, 500, 32, 20);
+            quicklistDelRange(ql, 60, 10);
+            ql_verify(ql, 16, 490, 32, 20);
+            quicklistRelease(ql);
+        }
+
+        TEST("delete negative 1 from 500 list") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistSetFill(ql, 32);
+            for (int i = 0; i < 500; i++)
+                quicklistPushTail(ql, genstr("hello", i + 1), 32);
+            ql_verify(ql, 16, 500, 32, 20);
+            quicklistDelRange(ql, -1, 1);
+            ql_verify(ql, 16, 499, 32, 19);
+            quicklistRelease(ql);
+        }
+
+        TEST("delete negative 1 from 500 list with overflow counts") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistSetFill(ql, 32);
+            for (int i = 0; i < 500; i++)
+                quicklistPushTail(ql, genstr("hello", i + 1), 32);
+            ql_verify(ql, 16, 500, 32, 20);
+            quicklistDelRange(ql, -1, 128);
+            ql_verify(ql, 16, 499, 32, 19);
+            quicklistRelease(ql);
+        }
+
+        TEST("delete negative 100 from 500 list") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistSetFill(ql, 32);
+            for (int i = 0; i < 500; i++)
+                quicklistPushTail(ql, genstr("hello", i + 1), 32);
+            quicklistDelRange(ql, -100, 100);
+            ql_verify(ql, 13, 400, 32, 16);
+            quicklistRelease(ql);
+        }
+
+        TEST("delete -10 count 5 from 50 list") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistSetFill(ql, 32);
+            for (int i = 0; i < 50; i++)
+                quicklistPushTail(ql, genstr("hello", i + 1), 32);
+            ql_verify(ql, 2, 50, 32, 18);
+            quicklistDelRange(ql, -10, 5);
+            ql_verify(ql, 2, 45, 32, 13);
+            quicklistRelease(ql);
+        }
+
+        TEST("numbers only list read") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistPushTail(ql, "1111", 4);
+            quicklistPushTail(ql, "2222", 4);
+            quicklistPushTail(ql, "3333", 4);
+            quicklistPushTail(ql, "4444", 4);
+            ql_verify(ql, 1, 4, 4, 4);
+            quicklistEntry entry;
+            iter = quicklistGetIteratorEntryAtIdx(ql, 0, &entry);
+            if (entry.longval != 1111)
+                ERR("Not 1111, %lld", entry.longval);
+            ql_release_iterator(iter);
+
+            iter = quicklistGetIteratorEntryAtIdx(ql, 1, &entry);
+            if (entry.longval != 2222)
+                ERR("Not 2222, %lld", entry.longval);
+            ql_release_iterator(iter);
+
+            iter = quicklistGetIteratorEntryAtIdx(ql, 2, &entry);
+            if (entry.longval != 3333)
+                ERR("Not 3333, %lld", entry.longval);
+            ql_release_iterator(iter);
+
+            iter = quicklistGetIteratorEntryAtIdx(ql, 3, &entry);
+            if (entry.longval != 4444)
+                ERR("Not 4444, %lld", entry.longval);
+            ql_release_iterator(iter);
+
+            iter = quicklistGetIteratorEntryAtIdx(ql, 4, &entry);
+            if (iter)
+                ERR("Index past elements: %lld", entry.longval);
+            ql_release_iterator(iter);
+            
+            iter = quicklistGetIteratorEntryAtIdx(ql, -1, &entry);
+            if (entry.longval != 4444)
+                ERR("Not 4444 (reverse), %lld", entry.longval);
+            ql_release_iterator(iter);
+
+            iter = quicklistGetIteratorEntryAtIdx(ql, -2, &entry);
+            if (entry.longval != 3333)
+                ERR("Not 3333 (reverse), %lld", entry.longval);
+            ql_release_iterator(iter);
+
+            iter = quicklistGetIteratorEntryAtIdx(ql, -3, &entry);
+            if (entry.longval != 2222)
+                ERR("Not 2222 (reverse), %lld", entry.longval);
+            ql_release_iterator(iter);
+            
+            iter = quicklistGetIteratorEntryAtIdx(ql, -4, &entry);
+            if (entry.longval != 1111)
+                ERR("Not 1111 (reverse), %lld", entry.longval);
+            ql_release_iterator(iter);
+            
+            iter = quicklistGetIteratorEntryAtIdx(ql, -5, &entry);
+            if (iter)
+                ERR("Index past elements (reverse), %lld", entry.longval);
+            ql_release_iterator(iter);
+            quicklistRelease(ql);
+        }
+
+        TEST("numbers larger list read") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistSetFill(ql, 32);
+            char num[32];
+            long long nums[5000];
+            for (int i = 0; i < 5000; i++) {
+                nums[i] = -5157318210846258176 + i;
+                int sz = ll2string(num, sizeof(num), nums[i]);
+                quicklistPushTail(ql, num, sz);
+            }
+            quicklistPushTail(ql, "xxxxxxxxxxxxxxxxxxxx", 20);
+            quicklistEntry entry;
+            for (int i = 0; i < 5000; i++) {
+                iter = quicklistGetIteratorEntryAtIdx(ql, i, &entry);
+                if (entry.longval != nums[i])
+                    ERR("[%d] Not longval %lld but rather %lld", i, nums[i],
+                        entry.longval);
+                entry.longval = 0xdeadbeef;
+                ql_release_iterator(iter);
+            }
+            iter = quicklistGetIteratorEntryAtIdx(ql, 5000, &entry);
+            if (strncmp((char *)entry.value, "xxxxxxxxxxxxxxxxxxxx", 20))
+                ERR("String val not match: %s", entry.value);
+            ql_verify(ql, 157, 5001, 32, 9);
+            ql_release_iterator(iter);
+            quicklistRelease(ql);
+        }
+
+        TEST("numbers larger list read B") {
+            quicklist *ql = quicklistNew(-2, options[_i]);
+            quicklistPushTail(ql, "99", 2);
+            quicklistPushTail(ql, "98", 2);
+            quicklistPushTail(ql, "xxxxxxxxxxxxxxxxxxxx", 20);
+            quicklistPushTail(ql, "96", 2);
+            quicklistPushTail(ql, "95", 2);
+            quicklistReplaceAtIndex(ql, 1, "foo", 3);
+            quicklistReplaceAtIndex(ql, -1, "bar", 3);
+            quicklistRelease(ql);
+        }
+
+        TEST_DESC("lrem test at compress %d", options[_i]) {
+            for (int f = 0; f < fill_count; f++) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                char *words[] = {"abc", "foo", "bar",  "foobar", "foobared",
+                                 "zap", "bar", "test", "foo"};
+                char *result[] = {"abc", "foo",  "foobar", "foobared",
+                                  "zap", "test", "foo"};
+                char *resultB[] = {"abc",      "foo", "foobar",
+                                   "foobared", "zap", "test"};
+                for (int i = 0; i < 9; i++)
+                    quicklistPushTail(ql, words[i], strlen(words[i]));
+
+                /* lrem 0 bar */
+                quicklistIter *iter = quicklistGetIterator(ql, AL_START_HEAD);
+                quicklistEntry entry;
+                int i = 0;
+                while (quicklistNext(iter, &entry)) {
+                    if (quicklistCompare(&entry, (unsigned char *)"bar", 3)) {
+                        quicklistDelEntry(iter, &entry);
+                    }
+                    i++;
+                }
+                ql_release_iterator(iter);
+
+                /* check result of lrem 0 bar */
+                iter = quicklistGetIterator(ql, AL_START_HEAD);
+                i = 0;
+                while (quicklistNext(iter, &entry)) {
+                    /* Result must be: abc, foo, foobar, foobared, zap, test,
+                     * foo */
+                    int sz = entry.sz;
+                    if (strncmp((char *)entry.value, result[i], entry.sz)) {
+                        ERR("No match at position %d, got %.*s instead of %s",
+                            i, sz, entry.value, result[i]);
+                    }
+                    i++;
+                }
+                ql_release_iterator(iter);
+
+                quicklistPushTail(ql, "foo", 3);
+
+                /* lrem -2 foo */
+                iter = quicklistGetIterator(ql, AL_START_TAIL);
+                i = 0;
+                int del = 2;
+                while (quicklistNext(iter, &entry)) {
+                    if (quicklistCompare(&entry, (unsigned char *)"foo", 3)) {
+                        quicklistDelEntry(iter, &entry);
+                        del--;
+                    }
+                    if (!del)
+                        break;
+                    i++;
+                }
+                ql_release_iterator(iter);
+
+                /* check result of lrem -2 foo */
+                /* (we're ignoring the '2' part and still deleting all foo
+                 * because
+                 * we only have two foo) */
+                iter = quicklistGetIterator(ql, AL_START_TAIL);
+                i = 0;
+                size_t resB = sizeof(resultB) / sizeof(*resultB);
+                while (quicklistNext(iter, &entry)) {
+                    /* Result must be: abc, foo, foobar, foobared, zap, test,
+                     * foo */
+                    int sz = entry.sz;
+                    if (strncmp((char *)entry.value, resultB[resB - 1 - i],
+                                sz)) {
+                        ERR("No match at position %d, got %.*s instead of %s",
+                            i, sz, entry.value, resultB[resB - 1 - i]);
+                    }
+                    i++;
+                }
+
+                ql_release_iterator(iter);
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST_DESC("iterate reverse + delete at compress %d", options[_i]) {
+            for (int f = 0; f < fill_count; f++) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                quicklistPushTail(ql, "abc", 3);
+                quicklistPushTail(ql, "def", 3);
+                quicklistPushTail(ql, "hij", 3);
+                quicklistPushTail(ql, "jkl", 3);
+                quicklistPushTail(ql, "oop", 3);
+
+                quicklistEntry entry;
+                quicklistIter *iter = quicklistGetIterator(ql, AL_START_TAIL);
+                int i = 0;
+                while (quicklistNext(iter, &entry)) {
+                    if (quicklistCompare(&entry, (unsigned char *)"hij", 3)) {
+                        quicklistDelEntry(iter, &entry);
+                    }
+                    i++;
+                }
+                ql_release_iterator(iter);
+
+                if (i != 5)
+                    ERR("Didn't iterate 5 times, iterated %d times.", i);
+
+                /* Check results after deletion of "hij" */
+                iter = quicklistGetIterator(ql, AL_START_HEAD);
+                i = 0;
+                char *vals[] = {"abc", "def", "jkl", "oop"};
+                while (quicklistNext(iter, &entry)) {
+                    if (!quicklistCompare(&entry, (unsigned char *)vals[i],
+                                          3)) {
+                        ERR("Value at %d didn't match %s\n", i, vals[i]);
+                    }
+                    i++;
+                }
+                ql_release_iterator(iter);
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST_DESC("iterator at index test at compress %d", options[_i]) {
+            for (int f = 0; f < fill_count; f++) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                char num[32];
+                long long nums[5000];
+                for (int i = 0; i < 760; i++) {
+                    nums[i] = -5157318210846258176 + i;
+                    int sz = ll2string(num, sizeof(num), nums[i]);
+                    quicklistPushTail(ql, num, sz);
+                }
+
+                quicklistEntry entry;
+                quicklistIter *iter =
+                    quicklistGetIteratorAtIdx(ql, AL_START_HEAD, 437);
+                int i = 437;
+                while (quicklistNext(iter, &entry)) {
+                    if (entry.longval != nums[i])
+                        ERR("Expected %lld, but got %lld", entry.longval,
+                            nums[i]);
+                    i++;
+                }
+                ql_release_iterator(iter);
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST_DESC("ltrim test A at compress %d", options[_i]) {
+            for (int f = 0; f < fill_count; f++) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                char num[32];
+                long long nums[5000];
+                for (int i = 0; i < 32; i++) {
+                    nums[i] = -5157318210846258176 + i;
+                    int sz = ll2string(num, sizeof(num), nums[i]);
+                    quicklistPushTail(ql, num, sz);
+                }
+                if (fills[f] == 32)
+                    ql_verify(ql, 1, 32, 32, 32);
+                /* ltrim 25 53 (keep [25,32] inclusive = 7 remaining) */
+                quicklistDelRange(ql, 0, 25);
+                quicklistDelRange(ql, 0, 0);
+                quicklistEntry entry;
+                for (int i = 0; i < 7; i++) {
+                    iter = quicklistGetIteratorEntryAtIdx(ql, i, &entry);
+                    if (entry.longval != nums[25 + i])
+                        ERR("Deleted invalid range!  Expected %lld but got "
+                            "%lld",
+                            entry.longval, nums[25 + i]);
+                    ql_release_iterator(iter);
+                }
+                if (fills[f] == 32)
+                    ql_verify(ql, 1, 7, 7, 7);
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST_DESC("ltrim test B at compress %d", options[_i]) {
+            for (int f = 0; f < fill_count; f++) {
+                /* Force-disable compression because our 33 sequential
+                 * integers don't compress and the check always fails. */
+                quicklist *ql = quicklistNew(fills[f], QUICKLIST_NOCOMPRESS);
+                char num[32];
+                long long nums[5000];
+                for (int i = 0; i < 33; i++) {
+                    nums[i] = i;
+                    int sz = ll2string(num, sizeof(num), nums[i]);
+                    quicklistPushTail(ql, num, sz);
+                }
+                if (fills[f] == 32)
+                    ql_verify(ql, 2, 33, 32, 1);
+                /* ltrim 5 16 (keep [5,16] inclusive = 12 remaining) */
+                quicklistDelRange(ql, 0, 5);
+                quicklistDelRange(ql, -16, 16);
+                if (fills[f] == 32)
+                    ql_verify(ql, 1, 12, 12, 12);
+                quicklistEntry entry;
+
+                iter = quicklistGetIteratorEntryAtIdx(ql, 0, &entry);
+                if (entry.longval != 5)
+                    ERR("A: longval not 5, but %lld", entry.longval);
+                ql_release_iterator(iter);
+
+                iter = quicklistGetIteratorEntryAtIdx(ql, -1, &entry);
+                if (entry.longval != 16)
+                    ERR("B! got instead: %lld", entry.longval);
+                quicklistPushTail(ql, "bobobob", 7);
+                ql_release_iterator(iter);
+
+                iter = quicklistGetIteratorEntryAtIdx(ql, -1, &entry);
+                int sz = entry.sz;
+                if (strncmp((char *)entry.value, "bobobob", 7))
+                    ERR("Tail doesn't match bobobob, it's %.*s instead",
+                        sz, entry.value);
+                ql_release_iterator(iter);
+
+                for (int i = 0; i < 12; i++) {
+                    iter = quicklistGetIteratorEntryAtIdx(ql, i, &entry);
+                    if (entry.longval != nums[5 + i])
+                        ERR("Deleted invalid range!  Expected %lld but got "
+                            "%lld",
+                            entry.longval, nums[5 + i]);
+                    ql_release_iterator(iter);
+                }
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST_DESC("ltrim test C at compress %d", options[_i]) {
+            for (int f = 0; f < fill_count; f++) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                char num[32];
+                long long nums[5000];
+                for (int i = 0; i < 33; i++) {
+                    nums[i] = -5157318210846258176 + i;
+                    int sz = ll2string(num, sizeof(num), nums[i]);
+                    quicklistPushTail(ql, num, sz);
+                }
+                if (fills[f] == 32)
+                    ql_verify(ql, 2, 33, 32, 1);
+                /* ltrim 3 3 (keep [3,3] inclusive = 1 remaining) */
+                quicklistDelRange(ql, 0, 3);
+                quicklistDelRange(ql, -29,
+                                  4000); /* make sure not loop forever */
+                if (fills[f] == 32)
+                    ql_verify(ql, 1, 1, 1, 1);
+                quicklistEntry entry;
+                iter = quicklistGetIteratorEntryAtIdx(ql, 0, &entry);
+                if (entry.longval != -5157318210846258173)
+                    ERROR;
+                ql_release_iterator(iter);
+                quicklistRelease(ql);
+            }
+        }
+
+        TEST_DESC("ltrim test D at compress %d", options[_i]) {
+            for (int f = 0; f < fill_count; f++) {
+                quicklist *ql = quicklistNew(fills[f], options[_i]);
+                char num[32];
+                long long nums[5000];
+                for (int i = 0; i < 33; i++) {
+                    nums[i] = -5157318210846258176 + i;
+                    int sz = ll2string(num, sizeof(num), nums[i]);
+                    quicklistPushTail(ql, num, sz);
+                }
+                if (fills[f] == 32)
+                    ql_verify(ql, 2, 33, 32, 1);
+                quicklistDelRange(ql, -12, 3);
+                if (ql->count != 30)
+                    ERR("Didn't delete exactly three elements!  Count is: %lu",
+                        ql->count);
+                quicklistRelease(ql);
+            }
+        }
+
+        long long stop = mstime();
+        runtime[_i] = stop - start;
+    }
+
+    /* Run a longer test of compression depth outside of primary test loop. */
+    int list_sizes[] = {250, 251, 500, 999, 1000};
+    long long start = mstime();
+    int list_count = accurate ? (int)(sizeof(list_sizes) / sizeof(*list_sizes)) : 1;
+    for (int list = 0; list < list_count; list++) {
+        TEST_DESC("verify specific compression of interior nodes with %d list ",
+                  list_sizes[list]) {
+            for (int f = 0; f < fill_count; f++) {
+                for (int depth = 1; depth < 40; depth++) {
+                    /* skip over many redundant test cases */
+                    quicklist *ql = quicklistNew(fills[f], depth);
+                    for (int i = 0; i < list_sizes[list]; i++) {
+                        quicklistPushTail(ql, genstr("hello TAIL", i + 1), 64);
+                        quicklistPushHead(ql, genstr("hello HEAD", i + 1), 64);
+                    }
+
+                    for (int step = 0; step < 2; step++) {
+                        /* test remove node */
+                        if (step == 1) {
+                            for (int i = 0; i < list_sizes[list] / 2; i++) {
+                                unsigned char *data;
+                                assert(quicklistPop(ql, QUICKLIST_HEAD, &data,
+                                                    NULL, NULL));
+                                zfree(data);
+                                assert(quicklistPop(ql, QUICKLIST_TAIL, &data,
+                                                    NULL, NULL));
+                                zfree(data);
+                            }
+                        }
+                        quicklistNode *node = ql->head;
+                        unsigned int low_raw = ql->compress;
+                        unsigned int high_raw = ql->len - ql->compress;
+
+                        for (unsigned int at = 0; at < ql->len;
+                            at++, node = node->next) {
+                            if (at < low_raw || at >= high_raw) {
+                                if (node->encoding != QUICKLIST_NODE_ENCODING_RAW) {
+                                    ERR("Incorrect compression: node %d is "
+                                        "compressed at depth %d ((%u, %u); total "
+                                        "nodes: %lu; size: %zu)",
+                                        at, depth, low_raw, high_raw, ql->len,
+                                        node->sz);
+                                }
+                            } else {
+                                if (node->encoding != QUICKLIST_NODE_ENCODING_LZF) {
+                                    ERR("Incorrect non-compression: node %d is NOT "
+                                        "compressed at depth %d ((%u, %u); total "
+                                        "nodes: %lu; size: %zu; attempted: %d)",
+                                        at, depth, low_raw, high_raw, ql->len,
+                                        node->sz, node->attempted_compress);
+                                }
+                            }
+                        }
+                    }
+
+                    quicklistRelease(ql);
+                }
+            }
+        }
+    }
+    long long stop = mstime();
+
+    printf("\n");
+    for (size_t i = 0; i < option_count; i++)
+        printf("Test Loop %02d: %0.2f seconds.\n", options[i],
+               (float)runtime[i] / 1000);
+    printf("Compressions: %0.2f seconds.\n", (float)(stop - start) / 1000);
+    printf("\n");
+
+    TEST("bookmark get updated to next item") {
+        quicklist *ql = quicklistNew(1, 0);
+        quicklistPushTail(ql, "1", 1);
+        quicklistPushTail(ql, "2", 1);
+        quicklistPushTail(ql, "3", 1);
+        quicklistPushTail(ql, "4", 1);
+        quicklistPushTail(ql, "5", 1);
+        assert(ql->len==5);
+        /* add two bookmarks, one pointing to the node before the last. */
+        assert(quicklistBookmarkCreate(&ql, "_dummy", ql->head->next));
+        assert(quicklistBookmarkCreate(&ql, "_test", ql->tail->prev));
+        /* test that the bookmark returns the right node, delete it and see that the bookmark points to the last node */
+        assert(quicklistBookmarkFind(ql, "_test") == ql->tail->prev);
+        assert(quicklistDelRange(ql, -2, 1));
+        assert(quicklistBookmarkFind(ql, "_test") == ql->tail);
+        /* delete the last node, and see that the bookmark was deleted. */
+        assert(quicklistDelRange(ql, -1, 1));
+        assert(quicklistBookmarkFind(ql, "_test") == NULL);
+        /* test that other bookmarks aren't affected */
+        assert(quicklistBookmarkFind(ql, "_dummy") == ql->head->next);
+        assert(quicklistBookmarkFind(ql, "_missing") == NULL);
+        assert(ql->len==3);
+        quicklistBookmarksClear(ql); /* for coverage */
+        assert(quicklistBookmarkFind(ql, "_dummy") == NULL);
+        quicklistRelease(ql);
+    }
+
+    TEST("bookmark limit") {
+        int i;
+        quicklist *ql = quicklistNew(1, 0);
+        quicklistPushHead(ql, "1", 1);
+        for (i=0; i<QL_MAX_BM; i++)
+            assert(quicklistBookmarkCreate(&ql, genstr("",i), ql->head));
+        /* when all bookmarks are used, creation fails */
+        assert(!quicklistBookmarkCreate(&ql, "_test", ql->head));
+        /* delete one and see that we can now create another */
+        assert(quicklistBookmarkDelete(ql, "0"));
+        assert(quicklistBookmarkCreate(&ql, "_test", ql->head));
+        /* delete one and see that the rest survive */
+        assert(quicklistBookmarkDelete(ql, "_test"));
+        for (i=1; i<QL_MAX_BM; i++)
+            assert(quicklistBookmarkFind(ql, genstr("",i)) == ql->head);
+        /* make sure the deleted ones are indeed gone */
+        assert(!quicklistBookmarkFind(ql, "0"));
+        assert(!quicklistBookmarkFind(ql, "_test"));
+        quicklistRelease(ql);
+    }
+
+    if (flags & REDIS_TEST_LARGE_MEMORY) {
+        TEST("compress and decompress quicklist listpack node") {
+            quicklistNode *node = quicklistCreateNode();
+            node->entry = lpNew(0);
+
+            /* Just to avoid triggering the assertion in __quicklistCompressNode(),
+             * it disables the passing of quicklist head or tail node. */
+            node->prev = quicklistCreateNode();
+            node->next = quicklistCreateNode();
+            
+            /* Create a rand string */
+            size_t sz = (1 << 25); /* 32MB per one entry */
+            unsigned char *s = zmalloc(sz);
+            randstring(s, sz);
+
+            /* Keep filling the node, until it reaches 1GB */
+            for (int i = 0; i < 32; i++) {
+                node->entry = lpAppend(node->entry, s, sz);
+                quicklistNodeUpdateSz(node);
+
+                long long start = mstime();
+                assert(__quicklistCompressNode(node));
+                assert(__quicklistDecompressNode(node));
+                printf("Compress and decompress: %zu MB in %.2f seconds.\n",
+                       node->sz/1024/1024, (float)(mstime() - start) / 1000);
+            }
+
+            zfree(s);
+            zfree(node->prev);
+            zfree(node->next);
+            zfree(node->entry);
+            zfree(node);
+        }
+
+#if ULONG_MAX >= 0xffffffffffffffff
+        TEST("compress and decomress quicklist plain node large than UINT32_MAX") {
+            size_t sz = (1ull << 32);
+            unsigned char *s = zmalloc(sz);
+            randstring(s, sz);
+            memcpy(s, "helloworld", 10);
+            memcpy(s + sz - 10, "1234567890", 10);
+
+            quicklistNode *node = __quicklistCreatePlainNode(s, sz);
+
+            /* Just to avoid triggering the assertion in __quicklistCompressNode(),
+             * it disables the passing of quicklist head or tail node. */
+            node->prev = quicklistCreateNode();
+            node->next = quicklistCreateNode();
+
+            long long start = mstime();
+            assert(__quicklistCompressNode(node));
+            assert(__quicklistDecompressNode(node));
+            printf("Compress and decompress: %zu MB in %.2f seconds.\n",
+                   node->sz/1024/1024, (float)(mstime() - start) / 1000);
+
+            assert(memcmp(node->entry, "helloworld", 10) == 0);
+            assert(memcmp(node->entry + sz - 10, "1234567890", 10) == 0);
+            zfree(node->prev);
+            zfree(node->next);
+            zfree(node->entry);
+            zfree(node);
+        }
+#endif
+    }
+
+    if (!err)
+        printf("ALL TESTS PASSED!\n");
+    else
+        ERR("Sorry, not all tests passed!  In fact, %d tests failed.", err);
+
+    return err;
+}
+#endif