Adding upstream version 14.2.21.upstream/14.2.21upstream

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

1 files changed, 432 insertions, 0 deletions

diff --git a/src/rocksdb/utilities/transactions/write_prepared_txn.cc b/src/rocksdb/utilities/transactions/write_prepared_txn.cc
new file mode 100644
index 00000000..4100925c
--- /dev/null
+++ b/src/rocksdb/utilities/transactions/write_prepared_txn.cc
@@ -0,0 +1,432 @@
+//  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+
+#ifndef ROCKSDB_LITE
+
+#include "utilities/transactions/write_prepared_txn.h"
+
+#ifndef __STDC_FORMAT_MACROS
+#define __STDC_FORMAT_MACROS
+#endif
+
+#include <inttypes.h>
+#include <map>
+#include <set>
+
+#include "db/column_family.h"
+#include "db/db_impl.h"
+#include "rocksdb/db.h"
+#include "rocksdb/status.h"
+#include "rocksdb/utilities/transaction_db.h"
+#include "util/cast_util.h"
+#include "utilities/transactions/pessimistic_transaction.h"
+#include "utilities/transactions/write_prepared_txn_db.h"
+
+namespace rocksdb {
+
+struct WriteOptions;
+
+WritePreparedTxn::WritePreparedTxn(WritePreparedTxnDB* txn_db,
+                                   const WriteOptions& write_options,
+                                   const TransactionOptions& txn_options)
+    : PessimisticTransaction(txn_db, write_options, txn_options, false),
+      wpt_db_(txn_db) {
+  // Call Initialize outside PessimisticTransaction constructor otherwise it
+  // would skip overridden functions in WritePreparedTxn since they are not
+  // defined yet in the constructor of PessimisticTransaction
+  Initialize(txn_options);
+}
+
+void WritePreparedTxn::Initialize(const TransactionOptions& txn_options) {
+  PessimisticTransaction::Initialize(txn_options);
+  prepare_batch_cnt_ = 0;
+}
+
+Status WritePreparedTxn::Get(const ReadOptions& read_options,
+                             ColumnFamilyHandle* column_family,
+                             const Slice& key, PinnableSlice* pinnable_val) {
+  auto snapshot = read_options.snapshot;
+  auto snap_seq =
+      snapshot != nullptr ? snapshot->GetSequenceNumber() : kMaxSequenceNumber;
+  SequenceNumber min_uncommitted =
+      kMinUnCommittedSeq;  // by default disable the optimization
+  if (snapshot != nullptr) {
+    min_uncommitted =
+        static_cast_with_check<const SnapshotImpl, const Snapshot>(snapshot)
+            ->min_uncommitted_;
+  }
+
+  WritePreparedTxnReadCallback callback(wpt_db_, snap_seq, min_uncommitted);
+  return write_batch_.GetFromBatchAndDB(db_, read_options, column_family, key,
+                                        pinnable_val, &callback);
+}
+
+Iterator* WritePreparedTxn::GetIterator(const ReadOptions& options) {
+  // Make sure to get iterator from WritePrepareTxnDB, not the root db.
+  Iterator* db_iter = wpt_db_->NewIterator(options);
+  assert(db_iter);
+
+  return write_batch_.NewIteratorWithBase(db_iter);
+}
+
+Iterator* WritePreparedTxn::GetIterator(const ReadOptions& options,
+                                        ColumnFamilyHandle* column_family) {
+  // Make sure to get iterator from WritePrepareTxnDB, not the root db.
+  Iterator* db_iter = wpt_db_->NewIterator(options, column_family);
+  assert(db_iter);
+
+  return write_batch_.NewIteratorWithBase(column_family, db_iter);
+}
+
+Status WritePreparedTxn::PrepareInternal() {
+  WriteOptions write_options = write_options_;
+  write_options.disableWAL = false;
+  const bool WRITE_AFTER_COMMIT = true;
+  const bool kFirstPrepareBatch = true;
+  WriteBatchInternal::MarkEndPrepare(GetWriteBatch()->GetWriteBatch(), name_,
+                                     !WRITE_AFTER_COMMIT);
+  // For each duplicate key we account for a new sub-batch
+  prepare_batch_cnt_ = GetWriteBatch()->SubBatchCnt();
+  // Having AddPrepared in the PreReleaseCallback allows in-order addition of
+  // prepared entries to PreparedHeap and hence enables an optimization. Refer to
+  // SmallestUnCommittedSeq for more details.
+  AddPreparedCallback add_prepared_callback(
+      wpt_db_, db_impl_, prepare_batch_cnt_,
+      db_impl_->immutable_db_options().two_write_queues, kFirstPrepareBatch);
+  const bool DISABLE_MEMTABLE = true;
+  uint64_t seq_used = kMaxSequenceNumber;
+  Status s = db_impl_->WriteImpl(
+      write_options, GetWriteBatch()->GetWriteBatch(),
+      /*callback*/ nullptr, &log_number_, /*log ref*/ 0, !DISABLE_MEMTABLE,
+      &seq_used, prepare_batch_cnt_, &add_prepared_callback);
+  assert(!s.ok() || seq_used != kMaxSequenceNumber);
+  auto prepare_seq = seq_used;
+  SetId(prepare_seq);
+  return s;
+}
+
+Status WritePreparedTxn::CommitWithoutPrepareInternal() {
+  // For each duplicate key we account for a new sub-batch
+  const size_t batch_cnt = GetWriteBatch()->SubBatchCnt();
+  return CommitBatchInternal(GetWriteBatch()->GetWriteBatch(), batch_cnt);
+}
+
+Status WritePreparedTxn::CommitBatchInternal(WriteBatch* batch,
+                                             size_t batch_cnt) {
+  return wpt_db_->WriteInternal(write_options_, batch, batch_cnt, this);
+}
+
+Status WritePreparedTxn::CommitInternal() {
+  ROCKS_LOG_DETAILS(db_impl_->immutable_db_options().info_log,
+                    "CommitInternal prepare_seq: %" PRIu64, GetID());
+  // We take the commit-time batch and append the Commit marker.
+  // The Memtable will ignore the Commit marker in non-recovery mode
+  WriteBatch* working_batch = GetCommitTimeWriteBatch();
+  const bool empty = working_batch->Count() == 0;
+  WriteBatchInternal::MarkCommit(working_batch, name_);
+
+  const bool for_recovery = use_only_the_last_commit_time_batch_for_recovery_;
+  if (!empty && for_recovery) {
+    // When not writing to memtable, we can still cache the latest write batch.
+    // The cached batch will be written to memtable in WriteRecoverableState
+    // during FlushMemTable
+    WriteBatchInternal::SetAsLastestPersistentState(working_batch);
+  }
+
+  auto prepare_seq = GetId();
+  const bool includes_data = !empty && !for_recovery;
+  assert(prepare_batch_cnt_);
+  size_t commit_batch_cnt = 0;
+  if (UNLIKELY(includes_data)) {
+    ROCKS_LOG_WARN(db_impl_->immutable_db_options().info_log,
+                   "Duplicate key overhead");
+    SubBatchCounter counter(*wpt_db_->GetCFComparatorMap());
+    auto s = working_batch->Iterate(&counter);
+    assert(s.ok());
+    commit_batch_cnt = counter.BatchCount();
+  }
+  const bool disable_memtable = !includes_data;
+  const bool do_one_write =
+      !db_impl_->immutable_db_options().two_write_queues || disable_memtable;
+  WritePreparedCommitEntryPreReleaseCallback update_commit_map(
+      wpt_db_, db_impl_, prepare_seq, prepare_batch_cnt_, commit_batch_cnt);
+  // This is to call AddPrepared on CommitTimeWriteBatch
+  const bool kFirstPrepareBatch = true;
+  AddPreparedCallback add_prepared_callback(
+      wpt_db_, db_impl_, commit_batch_cnt,
+      db_impl_->immutable_db_options().two_write_queues, !kFirstPrepareBatch);
+  PreReleaseCallback* pre_release_callback;
+  if (do_one_write) {
+    pre_release_callback = &update_commit_map;
+  } else {
+    pre_release_callback = &add_prepared_callback;
+  }
+  uint64_t seq_used = kMaxSequenceNumber;
+  // Since the prepared batch is directly written to memtable, there is already
+  // a connection between the memtable and its WAL, so there is no need to
+  // redundantly reference the log that contains the prepared data.
+  const uint64_t zero_log_number = 0ull;
+  size_t batch_cnt = UNLIKELY(commit_batch_cnt) ? commit_batch_cnt : 1;
+  auto s = db_impl_->WriteImpl(write_options_, working_batch, nullptr, nullptr,
+                               zero_log_number, disable_memtable, &seq_used,
+                               batch_cnt, pre_release_callback);
+  assert(!s.ok() || seq_used != kMaxSequenceNumber);
+  const SequenceNumber commit_batch_seq = seq_used;
+  if (LIKELY(do_one_write || !s.ok())) {
+    if (LIKELY(s.ok())) {
+      // Note RemovePrepared should be called after WriteImpl that publishsed
+      // the seq. Otherwise SmallestUnCommittedSeq optimization breaks.
+      wpt_db_->RemovePrepared(prepare_seq, prepare_batch_cnt_);
+    }
+    if (UNLIKELY(!do_one_write)) {
+      wpt_db_->RemovePrepared(commit_batch_seq, commit_batch_cnt);
+    }
+    return s;
+  }  // else do the 2nd write to publish seq
+  // Note: the 2nd write comes with a performance penality. So if we have too
+  // many of commits accompanied with ComitTimeWriteBatch and yet we cannot
+  // enable use_only_the_last_commit_time_batch_for_recovery_ optimization,
+  // two_write_queues should be disabled to avoid many additional writes here.
+  const size_t kZeroData = 0;
+  // Update commit map only from the 2nd queue
+  WritePreparedCommitEntryPreReleaseCallback update_commit_map_with_aux_batch(
+      wpt_db_, db_impl_, prepare_seq, prepare_batch_cnt_, kZeroData,
+      commit_batch_seq, commit_batch_cnt);
+  WriteBatch empty_batch;
+  empty_batch.PutLogData(Slice());
+  // In the absence of Prepare markers, use Noop as a batch separator
+  WriteBatchInternal::InsertNoop(&empty_batch);
+  const bool DISABLE_MEMTABLE = true;
+  const size_t ONE_BATCH = 1;
+  const uint64_t NO_REF_LOG = 0;
+  s = db_impl_->WriteImpl(write_options_, &empty_batch, nullptr, nullptr,
+                          NO_REF_LOG, DISABLE_MEMTABLE, &seq_used, ONE_BATCH,
+                          &update_commit_map_with_aux_batch);
+  assert(!s.ok() || seq_used != kMaxSequenceNumber);
+  // Note RemovePrepared should be called after WriteImpl that publishsed the
+  // seq. Otherwise SmallestUnCommittedSeq optimization breaks.
+  wpt_db_->RemovePrepared(prepare_seq, prepare_batch_cnt_);
+  wpt_db_->RemovePrepared(commit_batch_seq, commit_batch_cnt);
+  return s;
+}
+
+Status WritePreparedTxn::RollbackInternal() {
+  ROCKS_LOG_WARN(db_impl_->immutable_db_options().info_log,
+                 "RollbackInternal prepare_seq: %" PRIu64, GetId());
+  WriteBatch rollback_batch;
+  assert(GetId() != kMaxSequenceNumber);
+  assert(GetId() > 0);
+  auto cf_map_shared_ptr = wpt_db_->GetCFHandleMap();
+  auto cf_comp_map_shared_ptr = wpt_db_->GetCFComparatorMap();
+  auto read_at_seq = kMaxSequenceNumber;
+  struct RollbackWriteBatchBuilder : public WriteBatch::Handler {
+    DBImpl* db_;
+    ReadOptions roptions;
+    WritePreparedTxnReadCallback callback;
+    WriteBatch* rollback_batch_;
+    std::map<uint32_t, const Comparator*>& comparators_;
+    std::map<uint32_t, ColumnFamilyHandle*>& handles_;
+    using CFKeys = std::set<Slice, SetComparator>;
+    std::map<uint32_t, CFKeys> keys_;
+    bool rollback_merge_operands_;
+    RollbackWriteBatchBuilder(
+        DBImpl* db, WritePreparedTxnDB* wpt_db, SequenceNumber snap_seq,
+        WriteBatch* dst_batch,
+        std::map<uint32_t, const Comparator*>& comparators,
+        std::map<uint32_t, ColumnFamilyHandle*>& handles,
+        bool rollback_merge_operands)
+        : db_(db),
+          callback(wpt_db, snap_seq),  // disable min_uncommitted optimization
+          rollback_batch_(dst_batch),
+          comparators_(comparators),
+          handles_(handles),
+          rollback_merge_operands_(rollback_merge_operands) {}
+
+    Status Rollback(uint32_t cf, const Slice& key) {
+      Status s;
+      CFKeys& cf_keys = keys_[cf];
+      if (cf_keys.size() == 0) {  // just inserted
+        auto cmp = comparators_[cf];
+        keys_[cf] = CFKeys(SetComparator(cmp));
+      }
+      auto it = cf_keys.insert(key);
+      if (it.second ==
+          false) {  // second is false if a element already existed.
+        return s;
+      }
+
+      PinnableSlice pinnable_val;
+      bool not_used;
+      auto cf_handle = handles_[cf];
+      s = db_->GetImpl(roptions, cf_handle, key, &pinnable_val, &not_used,
+                       &callback);
+      assert(s.ok() || s.IsNotFound());
+      if (s.ok()) {
+        s = rollback_batch_->Put(cf_handle, key, pinnable_val);
+        assert(s.ok());
+      } else if (s.IsNotFound()) {
+        // There has been no readable value before txn. By adding a delete we
+        // make sure that there will be none afterwards either.
+        s = rollback_batch_->Delete(cf_handle, key);
+        assert(s.ok());
+      } else {
+        // Unexpected status. Return it to the user.
+      }
+      return s;
+    }
+
+    Status PutCF(uint32_t cf, const Slice& key, const Slice& /*val*/) override {
+      return Rollback(cf, key);
+    }
+
+    Status DeleteCF(uint32_t cf, const Slice& key) override {
+      return Rollback(cf, key);
+    }
+
+    Status SingleDeleteCF(uint32_t cf, const Slice& key) override {
+      return Rollback(cf, key);
+    }
+
+    Status MergeCF(uint32_t cf, const Slice& key,
+                   const Slice& /*val*/) override {
+      if (rollback_merge_operands_) {
+        return Rollback(cf, key);
+      } else {
+        return Status::OK();
+      }
+    }
+
+    Status MarkNoop(bool) override { return Status::OK(); }
+    Status MarkBeginPrepare(bool) override { return Status::OK(); }
+    Status MarkEndPrepare(const Slice&) override { return Status::OK(); }
+    Status MarkCommit(const Slice&) override { return Status::OK(); }
+    Status MarkRollback(const Slice&) override {
+      return Status::InvalidArgument();
+    }
+
+   protected:
+    bool WriteAfterCommit() const override { return false; }
+  } rollback_handler(db_impl_, wpt_db_, read_at_seq, &rollback_batch,
+                     *cf_comp_map_shared_ptr.get(), *cf_map_shared_ptr.get(),
+                     wpt_db_->txn_db_options_.rollback_merge_operands);
+  auto s = GetWriteBatch()->GetWriteBatch()->Iterate(&rollback_handler);
+  assert(s.ok());
+  if (!s.ok()) {
+    return s;
+  }
+  // The Rollback marker will be used as a batch separator
+  WriteBatchInternal::MarkRollback(&rollback_batch, name_);
+  bool do_one_write = !db_impl_->immutable_db_options().two_write_queues;
+  const bool DISABLE_MEMTABLE = true;
+  const uint64_t NO_REF_LOG = 0;
+  uint64_t seq_used = kMaxSequenceNumber;
+  const size_t ONE_BATCH = 1;
+  const bool kFirstPrepareBatch = true;
+  // We commit the rolled back prepared batches. Although this is
+  // counter-intuitive, i) it is safe to do so, since the prepared batches are
+  // already canceled out by the rollback batch, ii) adding the commit entry to
+  // CommitCache will allow us to benefit from the existing mechanism in
+  // CommitCache that keeps an entry evicted due to max advance and yet overlaps
+  // with a live snapshot around so that the live snapshot properly skips the
+  // entry even if its prepare seq is lower than max_evicted_seq_.
+  AddPreparedCallback add_prepared_callback(
+      wpt_db_, db_impl_, ONE_BATCH,
+      db_impl_->immutable_db_options().two_write_queues, !kFirstPrepareBatch);
+  WritePreparedCommitEntryPreReleaseCallback update_commit_map(
+      wpt_db_, db_impl_, GetId(), prepare_batch_cnt_, ONE_BATCH);
+  PreReleaseCallback* pre_release_callback;
+  if (do_one_write) {
+    pre_release_callback = &update_commit_map;
+  } else {
+    pre_release_callback = &add_prepared_callback;
+  }
+  // Note: the rollback batch does not need AddPrepared since it is written to
+  // DB in one shot. min_uncommitted still works since it requires capturing
+  // data that is written to DB but not yet committed, while
+  // the rollback batch commits with PreReleaseCallback.
+  s = db_impl_->WriteImpl(write_options_, &rollback_batch, nullptr, nullptr,
+                          NO_REF_LOG, !DISABLE_MEMTABLE, &seq_used, ONE_BATCH,
+                          pre_release_callback);
+  assert(!s.ok() || seq_used != kMaxSequenceNumber);
+  if (!s.ok()) {
+    return s;
+  }
+  if (do_one_write) {
+    wpt_db_->RemovePrepared(GetId(), prepare_batch_cnt_);
+    return s;
+  }  // else do the 2nd write for commit
+  uint64_t rollback_seq = seq_used;
+  ROCKS_LOG_DETAILS(db_impl_->immutable_db_options().info_log,
+                    "RollbackInternal 2nd write rollback_seq: %" PRIu64,
+                    rollback_seq);
+  // Commit the batch by writing an empty batch to the queue that will release
+  // the commit sequence number to readers.
+  WritePreparedRollbackPreReleaseCallback update_commit_map_with_prepare(
+      wpt_db_, db_impl_, GetId(), rollback_seq, prepare_batch_cnt_);
+  WriteBatch empty_batch;
+  empty_batch.PutLogData(Slice());
+  // In the absence of Prepare markers, use Noop as a batch separator
+  WriteBatchInternal::InsertNoop(&empty_batch);
+  s = db_impl_->WriteImpl(write_options_, &empty_batch, nullptr, nullptr,
+                          NO_REF_LOG, DISABLE_MEMTABLE, &seq_used, ONE_BATCH,
+                          &update_commit_map_with_prepare);
+  assert(!s.ok() || seq_used != kMaxSequenceNumber);
+  ROCKS_LOG_DETAILS(db_impl_->immutable_db_options().info_log,
+                    "RollbackInternal (status=%s) commit: %" PRIu64,
+                    s.ToString().c_str(), GetId());
+  if (s.ok()) {
+    wpt_db_->RemovePrepared(GetId(), prepare_batch_cnt_);
+  }
+  wpt_db_->RemovePrepared(rollback_seq, ONE_BATCH);
+
+  return s;
+}
+
+Status WritePreparedTxn::ValidateSnapshot(ColumnFamilyHandle* column_family,
+                                          const Slice& key,
+                                          SequenceNumber* tracked_at_seq) {
+  assert(snapshot_);
+
+  SequenceNumber min_uncommitted =
+      static_cast_with_check<const SnapshotImpl, const Snapshot>(
+          snapshot_.get())
+          ->min_uncommitted_;
+  SequenceNumber snap_seq = snapshot_->GetSequenceNumber();
+  // tracked_at_seq is either max or the last snapshot with which this key was
+  // trackeed so there is no need to apply the IsInSnapshot to this comparison
+  // here as tracked_at_seq is not a prepare seq.
+  if (*tracked_at_seq <= snap_seq) {
+    // If the key has been previous validated at a sequence number earlier
+    // than the curent snapshot's sequence number, we already know it has not
+    // been modified.
+    return Status::OK();
+  }
+
+  *tracked_at_seq = snap_seq;
+
+  ColumnFamilyHandle* cfh =
+      column_family ? column_family : db_impl_->DefaultColumnFamily();
+
+  WritePreparedTxnReadCallback snap_checker(wpt_db_, snap_seq, min_uncommitted);
+  return TransactionUtil::CheckKeyForConflicts(db_impl_, cfh, key.ToString(),
+                                               snap_seq, false /* cache_only */,
+                                               &snap_checker, min_uncommitted);
+}
+
+void WritePreparedTxn::SetSnapshot() {
+  const bool kForWWConflictCheck = true;
+  SnapshotImpl* snapshot = wpt_db_->GetSnapshotInternal(kForWWConflictCheck);
+  SetSnapshotInternal(snapshot);
+}
+
+Status WritePreparedTxn::RebuildFromWriteBatch(WriteBatch* src_batch) {
+  auto ret = PessimisticTransaction::RebuildFromWriteBatch(src_batch);
+  prepare_batch_cnt_ = GetWriteBatch()->SubBatchCnt();
+  return ret;
+}
+
+}  // namespace rocksdb
+
+#endif  // ROCKSDB_LITE