Adding upstream version 1.37.1.upstream/1.37.1upstream

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

8 files changed, 2502 insertions, 0 deletions

diff --git a/tests/profile/Makefile b/tests/profile/Makefile
new file mode 100644
index 0000000..b3510e6
--- /dev/null
+++ b/tests/profile/Makefile
@@ -0,0 +1,51 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+COMMON_CFLAGS = -I ../../ -Wall -Wextra
+PROFILE_CFLAGS = -O1 -ggdb $(COMMON_CFLAGS)
+PERFORMANCE_CFLAGS = -O2 $(COMMON_CFLAGS)
+
+CFLAGS = $(PERFORMANCE_CFLAGS)
+
+LIBNETDATA_FILES = \
+    ../../libnetdata/popen/popen.o \
+    ../../libnetdata/storage_number/storage_number.o \
+    ../../libnetdata/avl/avl.o \
+    ../../libnetdata/socket/socket.o \
+    ../../libnetdata/os.o \
+    ../../libnetdata/clocks/clocks.o \
+    ../../libnetdata/procfile/procfile.o \
+    ../../libnetdata/statistical/statistical.o \
+    ../../libnetdata/eval/eval.o \
+    ../../libnetdata/threads/threads.o \
+    ../../libnetdata/dictionary/dictionary.o \
+    ../../libnetdata/simple_pattern/simple_pattern.o \
+    ../../libnetdata/url/url.o \
+    ../../libnetdata/config/appconfig.o \
+    ../../libnetdata/libnetdata.o \
+    ../../libnetdata/buffer/buffer.o \
+    ../../libnetdata/adaptive_resortable_list/adaptive_resortable_list.o \
+    ../../libnetdata/locks/locks.o \
+    ../../libnetdata/log/log.o \
+    $(NULL)
+
+COMMON_LDFLAGS = $(LIBNETDATA_FILES) -pthread -lm
+
+all: statsd-stress benchmark-procfile-parser test-eval benchmark-dictionary benchmark-value-pairs
+
+benchmark-procfile-parser: benchmark-procfile-parser.c
+	gcc ${CFLAGS} -o $@ $^ ${COMMON_LDFLAGS}
+
+benchmark-dictionary: benchmark-dictionary.c
+	gcc ${CFLAGS} -o $@ $^ ${COMMON_LDFLAGS}
+
+benchmark-value-pairs: benchmark-value-pairs.c
+	gcc ${CFLAGS} -o $@ $^ ${COMMON_LDFLAGS}
+
+statsd-stress: statsd-stress.c
+	gcc ${CFLAGS} -o $@ $^ ${COMMON_LDFLAGS}
+
+test-eval: test-eval.c
+	gcc ${CFLAGS} -o $@ $^ ${COMMON_LDFLAGS}
+
+clean:
+	rm -f benchmark-procfile-parser statsd-stress test-eval benchmark-dictionary benchmark-value-pairs
diff --git a/tests/profile/benchmark-dictionary.c b/tests/profile/benchmark-dictionary.c
new file mode 100644
index 0000000..7cc9ab0
--- /dev/null
+++ b/tests/profile/benchmark-dictionary.c
@@ -0,0 +1,130 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * 1. build netdata (as normally)
+ * 2. cd tests/profile/
+ * 3. compile with:
+ *    gcc -O3 -Wall -Wextra -I ../../src/ -I ../../ -o benchmark-dictionary benchmark-dictionary.c ../../src/dictionary.o ../../src/log.o ../../src/avl.o ../../src/common.o -pthread
+ *
+ */
+
+#include "config.h"
+#include "libnetdata/libnetdata.h"
+
+struct myvalue {
+	int i;
+};
+
+void netdata_cleanup_and_exit(int ret) { exit(ret); }
+
+int main(int argc, char **argv) {
+	if(argc || argv) {;}
+
+//	DICTIONARY *dict = dictionary_create(DICT_OPTION_SINGLE_THREADED|DICT_OPTION_WITH_STATISTICS);
+	DICTIONARY *dict = dictionary_create(DICT_OPTION_STATS);
+	if(!dict) fatal("Cannot create dictionary.");
+
+	struct rusage start, end;
+	unsigned long long dt;
+	char buf[100 + 1];
+	struct myvalue value, *v;
+	int i, max = 30000000, max2;
+
+	// ------------------------------------------------------------------------
+
+	getrusage(RUSAGE_SELF, &start);
+	dict->stats->inserts = dict->stats->deletes = dict->stats->searches = 0ULL;
+	fprintf(stderr, "Inserting %d entries in the dictionary\n", max);
+	for(i = 0; i < max; i++) {
+		value.i = i;
+		snprintf(buf, 100, "%d", i);
+
+		dictionary_set(dict, buf, &value, sizeof(struct myvalue));
+	}
+	getrusage(RUSAGE_SELF, &end);
+	dt = (end.ru_utime.tv_sec * 1000000ULL + end.ru_utime.tv_usec) - (start.ru_utime.tv_sec * 1000000ULL + start.ru_utime.tv_usec);
+	fprintf(stderr, "Added %d entries in %llu nanoseconds: %llu inserts per second\n", max, dt, max * 1000000ULL / dt);
+	fprintf(stderr, " > Dictionary: %llu inserts, %llu deletes, %llu searches\n\n", dict->stats->inserts, dict->stats->deletes, dict->stats->searches);
+
+	// ------------------------------------------------------------------------
+
+	getrusage(RUSAGE_SELF, &start);
+	dict->stats->inserts = dict->stats->deletes = dict->stats->searches = 0ULL;
+	fprintf(stderr, "Retrieving %d entries from the dictionary\n", max);
+	for(i = 0; i < max; i++) {
+		value.i = i;
+		snprintf(buf, 100, "%d", i);
+
+		v = dictionary_get(dict, buf);
+		if(!v)
+			fprintf(stderr, "ERROR: cannot get value %d from the dictionary\n", i);
+		else if(v->i != i)
+			fprintf(stderr, "ERROR: expected %d but got %d\n", i, v->i);
+	}
+	getrusage(RUSAGE_SELF, &end);
+	dt = (end.ru_utime.tv_sec * 1000000ULL + end.ru_utime.tv_usec) - (start.ru_utime.tv_sec * 1000000ULL + start.ru_utime.tv_usec);
+	fprintf(stderr, "Read %d entries in %llu nanoseconds: %llu searches per second\n", max, dt, max * 1000000ULL / dt);
+	fprintf(stderr, " > Dictionary: %llu inserts, %llu deletes, %llu searches\n\n", dict->stats->inserts, dict->stats->deletes, dict->stats->searches);
+
+	// ------------------------------------------------------------------------
+
+	getrusage(RUSAGE_SELF, &start);
+	dict->stats->inserts = dict->stats->deletes = dict->stats->searches = 0ULL;
+	fprintf(stderr, "Resetting %d entries in the dictionary\n", max);
+	for(i = 0; i < max; i++) {
+		value.i = i;
+		snprintf(buf, 100, "%d", i);
+
+		dictionary_set(dict, buf, &value, sizeof(struct myvalue));
+	}
+	getrusage(RUSAGE_SELF, &end);
+	dt = (end.ru_utime.tv_sec * 1000000ULL + end.ru_utime.tv_usec) - (start.ru_utime.tv_sec * 1000000ULL + start.ru_utime.tv_usec);
+	fprintf(stderr, "Reset %d entries in %llu nanoseconds: %llu resets per second\n", max, dt, max * 1000000ULL / dt);
+	fprintf(stderr, " > Dictionary: %llu inserts, %llu deletes, %llu searches\n\n", dict->stats->inserts, dict->stats->deletes, dict->stats->searches);
+
+	// ------------------------------------------------------------------------
+
+	getrusage(RUSAGE_SELF, &start);
+	dict->stats->inserts = dict->stats->deletes = dict->stats->searches = 0ULL;
+	fprintf(stderr, "Searching  %d non-existing entries in the dictionary\n", max);
+	max2 = max * 2;
+	for(i = max; i < max2; i++) {
+		value.i = i;
+		snprintf(buf, 100, "%d", i);
+
+		v = dictionary_get(dict, buf);
+		if(v)
+			fprintf(stderr, "ERROR: cannot got non-existing value %d from the dictionary\n", i);
+	}
+	getrusage(RUSAGE_SELF, &end);
+	dt = (end.ru_utime.tv_sec * 1000000ULL + end.ru_utime.tv_usec) - (start.ru_utime.tv_sec * 1000000ULL + start.ru_utime.tv_usec);
+	fprintf(stderr, "Searched %d non-existing entries in %llu nanoseconds: %llu not found searches per second\n", max, dt, max * 1000000ULL / dt);
+	fprintf(stderr, " > Dictionary: %llu inserts, %llu deletes, %llu searches\n\n", dict->stats->inserts, dict->stats->deletes, dict->stats->searches);
+
+	// ------------------------------------------------------------------------
+
+	getrusage(RUSAGE_SELF, &start);
+	dict->stats->inserts = dict->stats->deletes = dict->stats->searches = 0ULL;
+	fprintf(stderr, "Deleting %d entries from the dictionary\n", max);
+	for(i = 0; i < max; i++) {
+		value.i = i;
+		snprintf(buf, 100, "%d", i);
+
+		dictionary_del(dict, buf);
+	}
+	getrusage(RUSAGE_SELF, &end);
+	dt = (end.ru_utime.tv_sec * 1000000ULL + end.ru_utime.tv_usec) - (start.ru_utime.tv_sec * 1000000ULL + start.ru_utime.tv_usec);
+	fprintf(stderr, "Deleted %d entries in %llu nanoseconds: %llu deletes per second\n", max, dt, max * 1000000ULL / dt);
+	fprintf(stderr, " > Dictionary: %llu inserts, %llu deletes, %llu searches\n\n", dict->stats->inserts, dict->stats->deletes, dict->stats->searches);
+
+	// ------------------------------------------------------------------------
+
+	getrusage(RUSAGE_SELF, &start);
+	dict->stats->inserts = dict->stats->deletes = dict->stats->searches = 0ULL;
+	fprintf(stderr, "Destroying dictionary\n");
+	dictionary_destroy(dict);
+	getrusage(RUSAGE_SELF, &end);
+	dt = (end.ru_utime.tv_sec * 1000000ULL + end.ru_utime.tv_usec) - (start.ru_utime.tv_sec * 1000000ULL + start.ru_utime.tv_usec);
+	fprintf(stderr, "Destroyed in %llu nanoseconds\n", dt);
+
+	return 0;
+}
diff --git a/tests/profile/benchmark-line-parsing.c b/tests/profile/benchmark-line-parsing.c
new file mode 100644
index 0000000..1d47cc8
--- /dev/null
+++ b/tests/profile/benchmark-line-parsing.c
@@ -0,0 +1,702 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+#include <stdio.h>
+#include <inttypes.h>
+#include <string.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <sys/time.h>
+
+#define likely(x) __builtin_expect(!!(x), 1)
+#define unlikely(x) __builtin_expect(!!(x), 0)
+
+#define simple_hash(name) ({                                         \
+    register unsigned char *__hash_source = (unsigned char *)(name); \
+    register uint32_t __hash_value = 0x811c9dc5;                     \
+    while (*__hash_source) {                                         \
+        __hash_value *= 16777619;                                    \
+        __hash_value ^= (uint32_t) *__hash_source++;                 \
+    }                                                                \
+    __hash_value;                                                    \
+})
+
+static inline uint32_t simple_hash2(const char *name) {
+    register unsigned char *s = (unsigned char *)name;
+    register uint32_t hval = 0x811c9dc5;
+    while (*s) {
+        hval *= 16777619;
+        hval ^= (uint32_t) *s++;
+    }
+    return hval;
+}
+
+static inline unsigned long long fast_strtoull(const char *s) {
+  register unsigned long long n = 0;
+  register char c;
+  for(c = *s; c >= '0' && c <= '9' ; c = *(++s)) {
+    n *= 10;
+    n += c - '0';
+    // n = (n << 1) + (n << 3) + (c - '0');
+  }
+  return n;
+}
+
+static uint32_t cache_hash = 0;
+static uint32_t rss_hash = 0;
+static uint32_t rss_huge_hash = 0;
+static uint32_t mapped_file_hash = 0;
+static uint32_t writeback_hash = 0;
+static uint32_t dirty_hash = 0;
+static uint32_t swap_hash = 0;
+static uint32_t pgpgin_hash = 0;
+static uint32_t pgpgout_hash = 0;
+static uint32_t pgfault_hash = 0;
+static uint32_t pgmajfault_hash = 0;
+static uint32_t inactive_anon_hash = 0;
+static uint32_t active_anon_hash = 0;
+static uint32_t inactive_file_hash = 0;
+static uint32_t active_file_hash = 0;
+static uint32_t unevictable_hash = 0;
+static uint32_t hierarchical_memory_limit_hash = 0;
+static uint32_t total_cache_hash = 0;
+static uint32_t total_rss_hash = 0;
+static uint32_t total_rss_huge_hash = 0;
+static uint32_t total_mapped_file_hash = 0;
+static uint32_t total_writeback_hash = 0;
+static uint32_t total_dirty_hash = 0;
+static uint32_t total_swap_hash = 0;
+static uint32_t total_pgpgin_hash = 0;
+static uint32_t total_pgpgout_hash = 0;
+static uint32_t total_pgfault_hash = 0;
+static uint32_t total_pgmajfault_hash = 0;
+static uint32_t total_inactive_anon_hash = 0;
+static uint32_t total_active_anon_hash = 0;
+static uint32_t total_inactive_file_hash = 0;
+static uint32_t total_active_file_hash = 0;
+static uint32_t total_unevictable_hash = 0;
+
+char *strings[] = {
+  "cache",
+  "rss",
+  "rss_huge",
+  "mapped_file",
+  "writeback",
+  "dirty",
+  "swap",
+  "pgpgin",
+  "pgpgout",
+  "pgfault",
+  "pgmajfault",
+  "inactive_anon",
+  "active_anon",
+  "inactive_file",
+  "active_file",
+  "unevictable",
+  "hierarchical_memory_limit",
+  "total_cache",
+  "total_rss",
+  "total_rss_huge",
+  "total_mapped_file",
+  "total_writeback",
+  "total_dirty",
+  "total_swap",
+  "total_pgpgin",
+  "total_pgpgout",
+  "total_pgfault",
+  "total_pgmajfault",
+  "total_inactive_anon",
+  "total_active_anon",
+  "total_inactive_file",
+  "total_active_file",
+  "total_unevictable",
+  NULL
+};
+
+unsigned long long values1[12] = { 0 };
+unsigned long long values2[12] = { 0 };
+unsigned long long values3[12] = { 0 };
+unsigned long long values4[12] = { 0 };
+unsigned long long values5[12] = { 0 };
+unsigned long long values6[12] = { 0 };
+
+#define NUMBER1  "12345678901234"
+#define NUMBER2  "23456789012345"
+#define NUMBER3  "34567890123456"
+#define NUMBER4  "45678901234567"
+#define NUMBER5  "56789012345678"
+#define NUMBER6  "67890123456789"
+#define NUMBER7  "78901234567890"
+#define NUMBER8  "89012345678901"
+#define NUMBER9  "90123456789012"
+#define NUMBER10 "12345678901234"
+#define NUMBER11 "23456789012345"
+
+// simple system strcmp()
+void test1() {
+  int i;
+  for(i = 0; strings[i] ; i++) {
+    char *s = strings[i];
+
+    if(unlikely(!strcmp(s, "cache")))
+      values1[i] = strtoull(NUMBER1, NULL, 10);
+
+    else if(unlikely(!strcmp(s, "rss")))
+      values1[i] = strtoull(NUMBER2, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "rss_huge")))
+      values1[i] = strtoull(NUMBER3, NULL, 10);
+  
+    else if(unlikely(!strcmp(s, "mapped_file")))
+      values1[i] = strtoull(NUMBER4, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "writeback")))
+      values1[i] = strtoull(NUMBER5, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "dirty")))
+      values1[i] = strtoull(NUMBER6, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "swap")))
+      values1[i] = strtoull(NUMBER7, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "pgpgin")))
+      values1[i] = strtoull(NUMBER8, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "pgpgout")))
+      values1[i] = strtoull(NUMBER9, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "pgfault")))
+      values1[i] = strtoull(NUMBER10, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "pgmajfault")))
+      values1[i] = strtoull(NUMBER11, NULL, 10);
+  }
+}
+
+// inline simple_hash() with system strtoull()
+void test2() {
+  int i;
+  for(i = 0; strings[i] ; i++) {
+    char *s = strings[i];
+    uint32_t hash = simple_hash2(s);
+
+    if(unlikely(hash == cache_hash && !strcmp(s, "cache")))
+      values2[i] = strtoull(NUMBER1, NULL, 10);
+    
+    else if(unlikely(hash == rss_hash && !strcmp(s, "rss")))
+      values2[i] = strtoull(NUMBER2, NULL, 10);
+    
+    else if(unlikely(hash == rss_huge_hash && !strcmp(s, "rss_huge")))
+      values2[i] = strtoull(NUMBER3, NULL, 10);
+    
+    else if(unlikely(hash == mapped_file_hash && !strcmp(s, "mapped_file")))
+      values2[i] = strtoull(NUMBER4, NULL, 10);
+    
+    else if(unlikely(hash == writeback_hash && !strcmp(s, "writeback")))
+      values2[i] = strtoull(NUMBER5, NULL, 10);
+    
+    else if(unlikely(hash == dirty_hash && !strcmp(s, "dirty")))
+      values2[i] = strtoull(NUMBER6, NULL, 10);
+    
+    else if(unlikely(hash == swap_hash && !strcmp(s, "swap")))
+      values2[i] = strtoull(NUMBER7, NULL, 10);
+  
+    else if(unlikely(hash == pgpgin_hash && !strcmp(s, "pgpgin")))
+      values2[i] = strtoull(NUMBER8, NULL, 10);
+    
+    else if(unlikely(hash == pgpgout_hash && !strcmp(s, "pgpgout")))
+      values2[i] = strtoull(NUMBER9, NULL, 10);
+    
+    else if(unlikely(hash == pgfault_hash && !strcmp(s, "pgfault")))
+      values2[i] = strtoull(NUMBER10, NULL, 10);
+    
+    else if(unlikely(hash == pgmajfault_hash && !strcmp(s, "pgmajfault")))
+      values2[i] = strtoull(NUMBER11, NULL, 10);
+  }
+}
+
+// statement expression simple_hash(), system strtoull()
+void test3() {
+  int i;
+  for(i = 0; strings[i] ; i++) {
+    char *s = strings[i];
+    uint32_t hash = simple_hash(s);
+
+    if(unlikely(hash == cache_hash && !strcmp(s, "cache")))
+      values3[i] = strtoull(NUMBER1, NULL, 10);
+    
+    else if(unlikely(hash == rss_hash && !strcmp(s, "rss")))
+      values3[i] = strtoull(NUMBER2, NULL, 10);
+    
+    else if(unlikely(hash == rss_huge_hash && !strcmp(s, "rss_huge")))
+      values3[i] = strtoull(NUMBER3, NULL, 10);
+    
+    else if(unlikely(hash == mapped_file_hash && !strcmp(s, "mapped_file")))
+      values3[i] = strtoull(NUMBER4, NULL, 10);
+    
+    else if(unlikely(hash == writeback_hash && !strcmp(s, "writeback")))
+      values3[i] = strtoull(NUMBER5, NULL, 10);
+    
+    else if(unlikely(hash == dirty_hash && !strcmp(s, "dirty")))
+      values3[i] = strtoull(NUMBER6, NULL, 10);
+    
+    else if(unlikely(hash == swap_hash && !strcmp(s, "swap")))
+      values3[i] = strtoull(NUMBER7, NULL, 10);
+    
+    else if(unlikely(hash == pgpgin_hash && !strcmp(s, "pgpgin")))
+      values3[i] = strtoull(NUMBER8, NULL, 10);
+    
+    else if(unlikely(hash == pgpgout_hash && !strcmp(s, "pgpgout")))
+      values3[i] = strtoull(NUMBER9, NULL, 10);
+    
+    else if(unlikely(hash == pgfault_hash && !strcmp(s, "pgfault")))
+      values3[i] = strtoull(NUMBER10, NULL, 10);
+    
+    else if(unlikely(hash == pgmajfault_hash && !strcmp(s, "pgmajfault")))
+      values3[i] = strtoull(NUMBER11, NULL, 10);
+  }
+}
+
+
+// inline simple_hash(), if-continue checks
+void test4() {
+  int i;
+  for(i = 0; strings[i] ; i++) {
+    char *s = strings[i];
+    uint32_t hash = simple_hash2(s);
+
+    if(unlikely(hash == cache_hash && !strcmp(s, "cache"))) {
+      values4[i] = strtoull(NUMBER1, NULL, 0);
+      continue;
+    }
+
+    if(unlikely(hash == rss_hash && !strcmp(s, "rss"))) {
+      values4[i] = strtoull(NUMBER2, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == rss_huge_hash && !strcmp(s, "rss_huge"))) {
+      values4[i] = strtoull(NUMBER3, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == mapped_file_hash && !strcmp(s, "mapped_file"))) {
+      values4[i] = strtoull(NUMBER4, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == writeback_hash && !strcmp(s, "writeback"))) {
+      values4[i] = strtoull(NUMBER5, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == dirty_hash && !strcmp(s, "dirty"))) {
+      values4[i] = strtoull(NUMBER6, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == swap_hash && !strcmp(s, "swap"))) {
+      values4[i] = strtoull(NUMBER7, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == pgpgin_hash && !strcmp(s, "pgpgin"))) {
+      values4[i] = strtoull(NUMBER8, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == pgpgout_hash && !strcmp(s, "pgpgout"))) {
+      values4[i] = strtoull(NUMBER9, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == pgfault_hash && !strcmp(s, "pgfault"))) {
+      values4[i] = strtoull(NUMBER10, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == pgmajfault_hash && !strcmp(s, "pgmajfault"))) {
+      values4[i] = strtoull(NUMBER11, NULL, 0);
+      continue;
+    }
+  }
+}
+
+// inline simple_hash(), if-else-if-else-if (netdata default)
+void test5() {
+  int i;
+  for(i = 0; strings[i] ; i++) {
+    char *s = strings[i];
+    uint32_t hash = simple_hash2(s);
+
+    if(unlikely(hash == cache_hash && !strcmp(s, "cache")))
+      values5[i] = fast_strtoull(NUMBER1);
+    
+    else if(unlikely(hash == rss_hash && !strcmp(s, "rss")))
+      values5[i] = fast_strtoull(NUMBER2);
+    
+    else if(unlikely(hash == rss_huge_hash && !strcmp(s, "rss_huge")))
+      values5[i] = fast_strtoull(NUMBER3);
+    
+    else if(unlikely(hash == mapped_file_hash && !strcmp(s, "mapped_file")))
+      values5[i] = fast_strtoull(NUMBER4);
+    
+    else if(unlikely(hash == writeback_hash && !strcmp(s, "writeback")))
+      values5[i] = fast_strtoull(NUMBER5);
+    
+    else if(unlikely(hash == dirty_hash && !strcmp(s, "dirty")))
+      values5[i] = fast_strtoull(NUMBER6);
+    
+    else if(unlikely(hash == swap_hash && !strcmp(s, "swap")))
+      values5[i] = fast_strtoull(NUMBER7);
+  
+    else if(unlikely(hash == pgpgin_hash && !strcmp(s, "pgpgin")))
+      values5[i] = fast_strtoull(NUMBER8);
+    
+    else if(unlikely(hash == pgpgout_hash && !strcmp(s, "pgpgout")))
+      values5[i] = fast_strtoull(NUMBER9);
+    
+    else if(unlikely(hash == pgfault_hash && !strcmp(s, "pgfault")))
+      values5[i] = fast_strtoull(NUMBER10);
+    
+    else if(unlikely(hash == pgmajfault_hash && !strcmp(s, "pgmajfault")))
+      values5[i] = fast_strtoull(NUMBER11);
+  }
+}
+
+// ----------------------------------------------------------------------------
+
+struct entry {
+  char *name;
+  uint32_t hash;
+  int found;
+  void (*func)(void *data1, void *data2);
+  void *data1;
+  void *data2;
+  struct entry *prev, *next;
+};
+
+struct base {
+  int iteration;
+  int registered;
+  int wanted;
+  int found;
+  struct entry *entries, *last;
+};
+
+static inline void callback(void *data1, void *data2) {
+    char *string = data1;
+    unsigned long long *value = data2;
+    *value = fast_strtoull(string);
+}
+
+static inline void callback_system_strtoull(void *data1, void *data2) {
+    char *string = data1;
+    unsigned long long *value = data2;
+    *value = strtoull(string, NULL, 10);
+}
+
+
+static inline struct base *entry(struct base *base, const char *name, void *data1, void *data2, void (*func)(void *, void *)) {
+  if(!base)
+    base = calloc(1, sizeof(struct base));
+
+  struct entry *e = malloc(sizeof(struct entry));
+  e->name = strdup(name);
+  e->hash = simple_hash2(e->name);
+  e->data1 = data1;
+  e->data2 = data2;
+  e->func = func;
+  e->prev = NULL;
+  e->next = base->entries;
+
+  if(base->entries) base->entries->prev = e;
+  else base->last = e;
+
+  base->entries = e;
+  base->registered++;
+  base->wanted = base->registered;
+
+  return base;
+}
+
+static inline int check(struct base *base, const char *s) {
+  uint32_t hash = simple_hash2(s);
+
+  if(likely(!strcmp(s, base->last->name))) {
+    base->last->found = 1;
+    base->found++;
+    if(base->last->func) base->last->func(base->last->data1, base->last->data2);
+    base->last = base->last->next;
+
+    if(!base->last)
+      base->last = base->entries;
+
+    if(base->found == base->registered)
+      return 1;
+
+    return 0;
+  }
+
+  // find it
+  struct entry *e;
+  for(e = base->entries; e ; e = e->next)
+    if(e->hash == hash && !strcmp(e->name, s))
+      break;
+
+  if(e == base->last) {
+    printf("ERROR\n");
+    exit(1);
+  }
+
+  if(e) {
+    // found
+
+    // run it
+    if(e->func) e->func(e->data1, e->data2);
+
+    // unlink it
+    if(e->next) e->next->prev = e->prev;
+    if(e->prev) e->prev->next = e->next;
+
+    if(base->entries == e)
+      base->entries = e->next;
+  }
+  else {
+    // not found
+
+    // create it
+    e = calloc(1, sizeof(struct entry));
+    e->name = strdup(s);
+    e->hash = hash;
+  }
+
+  // link it here
+  e->next = base->last;
+  if(base->last) {
+    e->prev = base->last->prev;
+    base->last->prev = e;
+
+    if(base->entries == base->last)
+      base->entries = e;
+  }
+  else
+    e->prev = NULL;
+
+  if(e->prev)
+    e->prev->next = e;
+
+  base->last = e->next;
+  if(!base->last)
+    base->last = base->entries;
+
+  e->found = 1;
+  base->found++;
+
+  if(base->found == base->registered)
+    return 1;
+
+  printf("relinked '%s' after '%s' and before '%s': ", e->name, e->prev?e->prev->name:"NONE", e->next?e->next->name:"NONE");
+  for(e = base->entries; e ; e = e->next) printf("%s ", e->name);
+  printf("\n");
+
+  return 0;
+}
+
+static inline void begin(struct base *base) {
+
+  if(unlikely(base->iteration % 60) == 1) {
+    base->wanted = 0;
+    struct entry *e;
+    for(e = base->entries; e ; e = e->next)
+      if(e->found) base->wanted++;
+  }
+
+  base->iteration++;
+  base->last = base->entries;
+  base->found = 0;
+}
+
+void test6() {
+
+  static struct base *base = NULL;
+
+  if(unlikely(!base)) {
+    base = entry(base, "cache", NUMBER1, &values6[0], callback_system_strtoull);
+    base = entry(base, "rss", NUMBER2, &values6[1], callback_system_strtoull);
+    base = entry(base, "rss_huge", NUMBER3, &values6[2], callback_system_strtoull);
+    base = entry(base, "mapped_file", NUMBER4, &values6[3], callback_system_strtoull);
+    base = entry(base, "writeback", NUMBER5, &values6[4], callback_system_strtoull);
+    base = entry(base, "dirty", NUMBER6, &values6[5], callback_system_strtoull);
+    base = entry(base, "swap", NUMBER7, &values6[6], callback_system_strtoull);
+    base = entry(base, "pgpgin", NUMBER8, &values6[7], callback_system_strtoull);
+    base = entry(base, "pgpgout", NUMBER9, &values6[8], callback_system_strtoull);
+    base = entry(base, "pgfault", NUMBER10, &values6[9], callback_system_strtoull);
+    base = entry(base, "pgmajfault", NUMBER11, &values6[10], callback_system_strtoull);
+  }
+
+  begin(base);
+
+  int i;
+  for(i = 0; strings[i] ; i++) {
+    if(check(base, strings[i]))
+      break;
+  }
+}
+
+void test7() {
+
+    static struct base *base = NULL;
+
+    if(unlikely(!base)) {
+        base = entry(base, "cache", NUMBER1, &values6[0], callback);
+        base = entry(base, "rss", NUMBER2, &values6[1], callback);
+        base = entry(base, "rss_huge", NUMBER3, &values6[2], callback);
+        base = entry(base, "mapped_file", NUMBER4, &values6[3], callback);
+        base = entry(base, "writeback", NUMBER5, &values6[4], callback);
+        base = entry(base, "dirty", NUMBER6, &values6[5], callback);
+        base = entry(base, "swap", NUMBER7, &values6[6], callback);
+        base = entry(base, "pgpgin", NUMBER8, &values6[7], callback);
+        base = entry(base, "pgpgout", NUMBER9, &values6[8], callback);
+        base = entry(base, "pgfault", NUMBER10, &values6[9], callback);
+        base = entry(base, "pgmajfault", NUMBER11, &values6[10], callback);
+    }
+
+    begin(base);
+
+    int i;
+    for(i = 0; strings[i] ; i++) {
+        if(check(base, strings[i]))
+            break;
+    }
+}
+
+// ----------------------------------------------------------------------------
+
+
+// ==============
+// --- Poor man cycle counting.
+static unsigned long tsc;
+
+static void begin_tsc(void)
+{
+  unsigned long a, d;
+  asm volatile ("cpuid\nrdtsc" : "=a" (a), "=d" (d) : "0" (0) : "ebx", "ecx");
+  tsc = ((unsigned long)d << 32) | (unsigned long)a;
+}
+
+static unsigned long end_tsc(void)
+{
+  unsigned long a, d;
+  asm volatile ("rdtscp" : "=a" (a), "=d" (d) : : "ecx");
+  return (((unsigned long)d << 32) | (unsigned long)a) - tsc;
+}
+// ===============
+
+static unsigned long long clk;
+
+static void begin_clock() {
+    struct timeval tv;
+    if(unlikely(gettimeofday(&tv, NULL) == -1))
+        return;
+    clk = tv.tv_sec  * 1000000 + tv.tv_usec;
+}
+
+static unsigned long long end_clock() {
+    struct timeval tv;
+    if(unlikely(gettimeofday(&tv, NULL) == -1))
+        return -1;
+    return clk = tv.tv_sec  * 1000000 + tv.tv_usec - clk;
+}
+
+void main(void)
+{
+    cache_hash = simple_hash("cache");
+    rss_hash = simple_hash("rss");
+    rss_huge_hash = simple_hash("rss_huge");
+    mapped_file_hash = simple_hash("mapped_file");
+    writeback_hash = simple_hash("writeback");
+    dirty_hash = simple_hash("dirty");
+    swap_hash = simple_hash("swap");
+    pgpgin_hash = simple_hash("pgpgin");
+    pgpgout_hash = simple_hash("pgpgout");
+    pgfault_hash = simple_hash("pgfault");
+    pgmajfault_hash = simple_hash("pgmajfault");
+    inactive_anon_hash = simple_hash("inactive_anon");
+    active_anon_hash = simple_hash("active_anon");
+    inactive_file_hash = simple_hash("inactive_file");
+    active_file_hash = simple_hash("active_file");
+    unevictable_hash = simple_hash("unevictable");
+    hierarchical_memory_limit_hash = simple_hash("hierarchical_memory_limit");
+    total_cache_hash = simple_hash("total_cache");
+    total_rss_hash = simple_hash("total_rss");
+    total_rss_huge_hash = simple_hash("total_rss_huge");
+    total_mapped_file_hash = simple_hash("total_mapped_file");
+    total_writeback_hash = simple_hash("total_writeback");
+    total_dirty_hash = simple_hash("total_dirty");
+    total_swap_hash = simple_hash("total_swap");
+    total_pgpgin_hash = simple_hash("total_pgpgin");
+    total_pgpgout_hash = simple_hash("total_pgpgout");
+    total_pgfault_hash = simple_hash("total_pgfault");
+    total_pgmajfault_hash = simple_hash("total_pgmajfault");
+    total_inactive_anon_hash = simple_hash("total_inactive_anon");
+    total_active_anon_hash = simple_hash("total_active_anon");
+    total_inactive_file_hash = simple_hash("total_inactive_file");
+    total_active_file_hash = simple_hash("total_active_file");
+    total_unevictable_hash = simple_hash("total_unevictable");
+
+  unsigned long i, c1 = 0, c2 = 0, c3 = 0, c4 = 0, c5 = 0, c6 = 0, c7;
+  unsigned long max = 1000000;
+
+  // let the processor get up to speed
+  begin_clock();
+  for(i = 0; i <= max ;i++) test1();
+  c1 = end_clock();
+
+  begin_clock();
+  for(i = 0; i <= max ;i++) test1();
+  c1 = end_clock();
+
+  begin_clock();
+  for(i = 0; i <= max ;i++) test2();
+  c2 = end_clock();
+    
+  begin_clock();
+  for(i = 0; i <= max ;i++) test3();
+  c3 = end_clock();
+
+  begin_clock();
+  for(i = 0; i <= max ;i++) test4();
+  c4 = end_clock();
+
+  begin_clock();
+  for(i = 0; i <= max ;i++) test5();
+  c5 = end_clock();
+
+    begin_clock();
+    for(i = 0; i <= max ;i++) test6();
+    c6 = end_clock();
+
+    begin_clock();
+    for(i = 0; i <= max ;i++) test7();
+    c7 = end_clock();
+
+    for(i = 0; i < 11 ; i++)
+    printf("value %lu: %llu %llu %llu %llu %llu %llu\n", i, values1[i], values2[i], values3[i], values4[i], values5[i], values6[i]);
+  
+  printf("\n\nRESULTS\n");
+  printf("test1() in %lu usecs: if-else-if-else-if, simple strcmp() with system strtoull().\n"
+         "test2() in %lu usecs: inline simple_hash() if-else-if-else-if, with system strtoull().\n"
+         "test3() in %lu usecs: statement expression simple_hash(), system strtoull().\n"
+         "test4() in %lu usecs: inline simple_hash(), if-continue checks, system strtoull().\n"
+         "test5() in %lu usecs: inline simple_hash(), if-else-if-else-if, custom strtoull() (netdata default prior to ARL).\n"
+         "test6() in %lu usecs: adaptive re-sortable list, system strtoull() (wow!)\n"
+         "test7() in %lu usecs: adaptive re-sortable list, custom strtoull() (wow!)\n"
+         , c1
+         , c2
+         , c3
+         , c4
+         , c5
+         , c6
+         , c7
+         );
+
+}
diff --git a/tests/profile/benchmark-procfile-parser.c b/tests/profile/benchmark-procfile-parser.c
new file mode 100644
index 0000000..214ca94
--- /dev/null
+++ b/tests/profile/benchmark-procfile-parser.c
@@ -0,0 +1,329 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+
+#include "config.h"
+#include "libnetdata/libnetdata.h"
+
+void netdata_cleanup_and_exit(int ret) {
+	exit(ret);
+}
+
+#define PF_PREFIX "PROCFILE"
+#define PFWORDS_INCREASE_STEP 200
+#define PFLINES_INCREASE_STEP 10
+#define PROCFILE_INCREMENT_BUFFER 512
+extern size_t procfile_max_lines;
+extern size_t procfile_max_words;
+extern size_t procfile_max_allocation;
+
+
+static inline void pflines_reset(pflines *fl) {
+    // debug(D_PROCFILE, PF_PREFIX ":   resetting lines");
+
+    fl->len = 0;
+}
+
+static inline void pflines_free(pflines *fl) {
+    // debug(D_PROCFILE, PF_PREFIX ":   freeing lines");
+
+    freez(fl);
+}
+
+static inline void pfwords_reset(pfwords *fw) {
+    // debug(D_PROCFILE, PF_PREFIX ":   resetting words");
+    fw->len = 0;
+}
+
+
+static inline void pfwords_add(procfile *ff, char *str) {
+    // debug(D_PROCFILE, PF_PREFIX ":   adding word No %d: '%s'", fw->len, str);
+
+    pfwords *fw = ff->words;
+    if(unlikely(fw->len == fw->size)) {
+        // debug(D_PROCFILE, PF_PREFIX ":   expanding words");
+
+        ff->words = fw = reallocz(fw, sizeof(pfwords) + (fw->size + PFWORDS_INCREASE_STEP) * sizeof(char *));
+        fw->size += PFWORDS_INCREASE_STEP;
+    }
+
+    fw->words[fw->len++] = str;
+}
+
+NEVERNULL
+static inline size_t *pflines_add(procfile *ff) {
+    // debug(D_PROCFILE, PF_PREFIX ":   adding line %d at word %d", fl->len, first_word);
+
+    pflines *fl = ff->lines;
+    if(unlikely(fl->len == fl->size)) {
+        // debug(D_PROCFILE, PF_PREFIX ":   expanding lines");
+
+        ff->lines = fl = reallocz(fl, sizeof(pflines) + (fl->size + PFLINES_INCREASE_STEP) * sizeof(ffline));
+        fl->size += PFLINES_INCREASE_STEP;
+    }
+
+    ffline *ffl = &fl->lines[fl->len++];
+    ffl->words = 0;
+    ffl->first = ff->words->len;
+
+    return &ffl->words;
+}
+
+
+NOINLINE
+static void procfile_parser(procfile *ff) {
+    // debug(D_PROCFILE, PF_PREFIX ": Parsing file '%s'", ff->filename);
+
+    char  *s = ff->data                 // our current position
+        , *e = &ff->data[ff->len]       // the terminating null
+        , *t = ff->data;                // the first character of a word (or quoted / parenthesized string)
+
+                                        // the look up array to find our type of character
+    PF_CHAR_TYPE *separators = ff->separators;
+
+    char quote = 0;                     // the quote character - only when in quoted string
+    size_t opened = 0;                  // counts the number of open parenthesis
+
+    size_t *line_words = pflines_add(ff);
+
+    while(s < e) {
+        PF_CHAR_TYPE ct = separators[(unsigned char)(*s)];
+
+        // this is faster than a switch()
+        // read more here: http://lazarenko.me/switch/
+        switch(ct) {
+        	case PF_CHAR_IS_SEPARATOR:
+	            if(!quote && !opened) {
+	                if (s != t) {
+	                    // separator, but we have word before it
+	                    *s = '\0';
+	                    pfwords_add(ff, t);
+	                    (*line_words)++;
+	                }
+	                t = s + 1;
+	            }
+	            // fallthrough
+
+			case PF_CHAR_IS_WORD:
+				s++;
+				break;
+
+
+		    case PF_CHAR_IS_NEWLINE:
+		        // end of line
+
+		        *s = '\0';
+		        pfwords_add(ff, t);
+		        (*line_words)++;
+		        t = ++s;
+
+		        // debug(D_PROCFILE, PF_PREFIX ":   ended line %d with %d words", l, ff->lines->lines[l].words);
+
+		        line_words = pflines_add(ff);
+		    	break;
+
+		    case PF_CHAR_IS_QUOTE:
+		        if(unlikely(!quote && s == t)) {
+		            // quote opened at the beginning
+		            quote = *s;
+		            t = ++s;
+		        }
+		        else if(unlikely(quote && quote == *s)) {
+		            // quote closed
+		            quote = 0;
+
+		            *s = '\0';
+		            pfwords_add(ff, t);
+		            (*line_words)++;
+		            t = ++s;
+		        }
+		        else
+		            s++;
+		    	break;
+
+		    case PF_CHAR_IS_OPEN:
+		        if(s == t) {
+		            opened++;
+		            t = ++s;
+		        }
+		        else if(opened) {
+		            opened++;
+		            s++;
+		        }
+		        else
+		            s++;
+		    	break;
+
+		    case PF_CHAR_IS_CLOSE:
+		        if(opened) {
+		            opened--;
+
+		            if(!opened) {
+		                *s = '\0';
+		                pfwords_add(ff, t);
+		                (*line_words)++;
+		                t = ++s;
+		            }
+		            else
+		                s++;
+		        }
+		        else
+		            s++;
+		    	break;
+
+		    default:
+		        fatal("Internal Error: procfile_readall() does not handle all the cases.");
+    	}
+	}
+
+    if(likely(s > t && t < e)) {
+        // the last word
+        if(unlikely(ff->len >= ff->size)) {
+            // we are going to loose the last byte
+            s = &ff->data[ff->size - 1];
+        }
+
+        *s = '\0';
+        pfwords_add(ff, t);
+        (*line_words)++;
+        // t = ++s;
+    }
+}
+
+
+procfile *procfile_readall1(procfile *ff) {
+    // debug(D_PROCFILE, PF_PREFIX ": Reading file '%s'.", ff->filename);
+
+    ff->len = 0;    // zero the used size
+    ssize_t r = 1;  // read at least once
+    while(r > 0) {
+        ssize_t s = ff->len;
+        ssize_t x = ff->size - s;
+
+        if(unlikely(!x)) {
+            debug(D_PROCFILE, PF_PREFIX ": Expanding data buffer for file '%s'.", procfile_filename(ff));
+            ff = reallocz(ff, sizeof(procfile) + ff->size + PROCFILE_INCREMENT_BUFFER);
+            ff->size += PROCFILE_INCREMENT_BUFFER;
+        }
+
+        debug(D_PROCFILE, "Reading file '%s', from position %zd with length %zd", procfile_filename(ff), s, (ssize_t)(ff->size - s));
+        r = read(ff->fd, &ff->data[s], ff->size - s);
+        if(unlikely(r == -1)) {
+            if(unlikely(!(ff->flags & PROCFILE_FLAG_NO_ERROR_ON_FILE_IO))) error(PF_PREFIX ": Cannot read from file '%s' on fd %d", procfile_filename(ff), ff->fd);
+            procfile_close(ff);
+            return NULL;
+        }
+
+        ff->len += r;
+    }
+
+    // debug(D_PROCFILE, "Rewinding file '%s'", ff->filename);
+    if(unlikely(lseek(ff->fd, 0, SEEK_SET) == -1)) {
+        if(unlikely(!(ff->flags & PROCFILE_FLAG_NO_ERROR_ON_FILE_IO))) error(PF_PREFIX ": Cannot rewind on file '%s'.", procfile_filename(ff));
+        procfile_close(ff);
+        return NULL;
+    }
+
+    pflines_reset(ff->lines);
+    pfwords_reset(ff->words);
+    procfile_parser(ff);
+
+    if(unlikely(procfile_adaptive_initial_allocation)) {
+        if(unlikely(ff->len > procfile_max_allocation)) procfile_max_allocation = ff->len;
+        if(unlikely(ff->lines->len > procfile_max_lines)) procfile_max_lines = ff->lines->len;
+        if(unlikely(ff->words->len > procfile_max_words)) procfile_max_words = ff->words->len;
+    }
+
+    // debug(D_PROCFILE, "File '%s' updated.", ff->filename);
+    return ff;
+}
+
+
+
+
+
+
+
+
+// ==============
+// --- Poor man cycle counting.
+static unsigned long tsc;
+
+void begin_tsc(void)
+{
+  unsigned long a, d;
+  asm volatile ("cpuid\nrdtsc" : "=a" (a), "=d" (d) : "0" (0) : "ebx", "ecx");
+  tsc = ((unsigned long)d << 32) | (unsigned long)a;
+}
+
+unsigned long end_tsc(void)
+{
+  unsigned long a, d;
+  asm volatile ("rdtscp" : "=a" (a), "=d" (d) : : "ecx");
+  return (((unsigned long)d << 32) | (unsigned long)a) - tsc;
+}
+// ==============
+
+
+unsigned long test_netdata_internal(void) {
+	static procfile *ff = NULL;
+
+	ff = procfile_reopen(ff, "/proc/self/status", " \t:,-()/", PROCFILE_FLAG_NO_ERROR_ON_FILE_IO);
+	if(!ff) {
+		fprintf(stderr, "Failed to open filename\n");
+		exit(1);
+	}
+
+	begin_tsc();
+	ff = procfile_readall(ff);
+	unsigned long c = end_tsc();
+
+	if(!ff) {
+		fprintf(stderr, "Failed to read filename\n");
+		exit(1);
+	}
+
+	return c;
+}
+
+unsigned long test_method1(void) {
+	static procfile *ff = NULL;
+
+	ff = procfile_reopen(ff, "/proc/self/status", " \t:,-()/", PROCFILE_FLAG_NO_ERROR_ON_FILE_IO);
+	if(!ff) {
+		fprintf(stderr, "Failed to open filename\n");
+		exit(1);
+	}
+
+	begin_tsc();
+	ff = procfile_readall1(ff);
+	unsigned long c = end_tsc();
+
+	if(!ff) {
+		fprintf(stderr, "Failed to read filename\n");
+		exit(1);
+	}
+
+	return c;
+}
+
+//--- Test
+int main(int argc, char **argv)
+{
+	(void)argc; (void)argv;
+
+	int i, max = 1000000;
+
+	unsigned long c1 = 0;
+	test_netdata_internal();
+	for(i = 0; i < max ; i++)
+		c1 += test_netdata_internal();
+
+	unsigned long c2 = 0;
+	test_method1();
+	for(i = 0; i < max ; i++)
+		c2 += test_method1();
+
+	printf("netdata internal: completed in %lu cycles, %lu cycles per read, %0.2f %%.\n", c1, c1 / max, (float)c1 * 100.0 / (float)c1);
+	printf("method1         : completed in %lu cycles, %lu cycles per read, %0.2f %%.\n", c2, c2 / max, (float)c2 * 100.0 / (float)c1);
+
+	return 0;
+}
diff --git a/tests/profile/benchmark-registry.c b/tests/profile/benchmark-registry.c
new file mode 100644
index 0000000..cfed6d7
--- /dev/null
+++ b/tests/profile/benchmark-registry.c
@@ -0,0 +1,227 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+
+/*
+ * compile with
+ *  gcc -O1 -ggdb -Wall -Wextra -I ../src/ -I ../ -o benchmark-registry benchmark-registry.c ../src/dictionary.o ../src/log.o ../src/avl.o ../src/common.o ../src/appconfig.o ../src/web_buffer.o ../src/storage_number.o ../src/rrd.o ../src/health.o -pthread -luuid -lm -DHAVE_CONFIG_H -DVARLIB_DIR="\"/tmp\""
+ */
+
+char *hostname = "me";
+
+#include "../src/registry.c"
+
+void netdata_cleanup_and_exit(int ret) { exit(ret); }
+
+// ----------------------------------------------------------------------------
+// TESTS
+
+int test1(int argc, char **argv) {
+
+	void print_stats(uint32_t requests, unsigned long long start, unsigned long long end) {
+		fprintf(stderr, " > SPEED: %u requests served in %0.2f seconds ( >>> %llu per second <<< )\n",
+				requests, (end-start) / 1000000.0, (unsigned long long)requests * 1000000ULL / (end-start));
+
+		fprintf(stderr, " > DB   : persons %llu, machines %llu, unique URLs %llu, accesses %llu, URLs: for persons %llu, for machines %llu\n",
+				registry.persons_count, registry.machines_count, registry.urls_count, registry.usages_count,
+				registry.persons_urls_count, registry.machines_urls_count);
+	}
+
+	(void) argc;
+	(void) argv;
+
+	uint32_t u, users = 1000000;
+	uint32_t m, machines = 200000;
+	uint32_t machines2 = machines * 2;
+
+	char **users_guids = malloc(users * sizeof(char *));
+	char **machines_guids = malloc(machines2 * sizeof(char *));
+	char **machines_urls = malloc(machines2 * sizeof(char *));
+	unsigned long long start;
+
+	registry_init();
+
+	fprintf(stderr, "Generating %u machine guids\n", machines2);
+	for(m = 0; m < machines2 ;m++) {
+		uuid_t uuid;
+		machines_guids[m] = malloc(36+1);
+		uuid_generate(uuid);
+		uuid_unparse(uuid, machines_guids[m]);
+
+		char buf[FILENAME_MAX + 1];
+		snprintfz(buf, FILENAME_MAX, "http://%u.netdata.rocks/", m+1);
+		machines_urls[m] = strdup(buf);
+
+		// fprintf(stderr, "\tmachine %u: '%s', url: '%s'\n", m + 1, machines_guids[m], machines_urls[m]);
+	}
+
+	start = timems();
+	fprintf(stderr, "\nGenerating %u users accessing %u machines\n", users, machines);
+	m = 0;
+	time_t now = time(NULL);
+	for(u = 0; u < users ; u++) {
+		if(++m == machines) m = 0;
+
+		PERSON *p = registry_request_access(NULL, machines_guids[m], machines_urls[m], "test", now);
+		users_guids[u] = p->guid;
+	}
+	print_stats(u, start, timems());
+
+	start = timems();
+	fprintf(stderr, "\nAll %u users accessing again the same %u servers\n", users, machines);
+	m = 0;
+	now = time(NULL);
+	for(u = 0; u < users ; u++) {
+		if(++m == machines) m = 0;
+
+		PERSON *p = registry_request_access(users_guids[u], machines_guids[m], machines_urls[m], "test", now);
+
+		if(p->guid != users_guids[u])
+			fprintf(stderr, "ERROR: expected to get user guid '%s' but git '%s'", users_guids[u], p->guid);
+	}
+	print_stats(u, start, timems());
+
+	start = timems();
+	fprintf(stderr, "\nAll %u users accessing a new server, out of the %u servers\n", users, machines);
+	m = 1;
+	now = time(NULL);
+	for(u = 0; u < users ; u++) {
+		if(++m == machines) m = 0;
+
+		PERSON *p = registry_request_access(users_guids[u], machines_guids[m], machines_urls[m], "test", now);
+
+		if(p->guid != users_guids[u])
+			fprintf(stderr, "ERROR: expected to get user guid '%s' but git '%s'", users_guids[u], p->guid);
+	}
+	print_stats(u, start, timems());
+
+	start = timems();
+	fprintf(stderr, "\n%u random users accessing a random server, out of the %u servers\n", users, machines);
+	now = time(NULL);
+	for(u = 0; u < users ; u++) {
+		uint32_t tu = random() * users / RAND_MAX;
+		uint32_t tm = random() * machines / RAND_MAX;
+
+		PERSON *p = registry_request_access(users_guids[tu], machines_guids[tm], machines_urls[tm], "test", now);
+
+		if(p->guid != users_guids[tu])
+			fprintf(stderr, "ERROR: expected to get user guid '%s' but git '%s'", users_guids[tu], p->guid);
+	}
+	print_stats(u, start, timems());
+
+	start = timems();
+	fprintf(stderr, "\n%u random users accessing a random server, out of %u servers\n", users, machines2);
+	now = time(NULL);
+	for(u = 0; u < users ; u++) {
+		uint32_t tu = random() * users / RAND_MAX;
+		uint32_t tm = random() * machines2 / RAND_MAX;
+
+		PERSON *p = registry_request_access(users_guids[tu], machines_guids[tm], machines_urls[tm], "test", now);
+
+		if(p->guid != users_guids[tu])
+			fprintf(stderr, "ERROR: expected to get user guid '%s' but git '%s'", users_guids[tu], p->guid);
+	}
+	print_stats(u, start, timems());
+
+	for(m = 0; m < 10; m++) {
+		start = timems();
+		fprintf(stderr,
+				"\n%u random user accesses to a random server, out of %u servers,\n > using 1/10000 with a random url, 1/1000 with a mismatched url\n",
+				users * 2, machines2);
+		now = time(NULL);
+		for (u = 0; u < users * 2; u++) {
+			uint32_t tu = random() * users / RAND_MAX;
+			uint32_t tm = random() * machines2 / RAND_MAX;
+
+			char *url = machines_urls[tm];
+			char buf[FILENAME_MAX + 1];
+			if (random() % 10000 == 1234) {
+				snprintfz(buf, FILENAME_MAX, "http://random.%ld.netdata.rocks/", random());
+				url = buf;
+			}
+			else if (random() % 1000 == 123)
+				url = machines_urls[random() * machines2 / RAND_MAX];
+
+			PERSON *p = registry_request_access(users_guids[tu], machines_guids[tm], url, "test", now);
+
+			if (p->guid != users_guids[tu])
+				fprintf(stderr, "ERROR: expected to get user guid '%s' but git '%s'", users_guids[tu], p->guid);
+		}
+		print_stats(u, start, timems());
+	}
+
+	fprintf(stderr, "\n\nSAVE\n");
+	start = timems();
+	registry_save();
+	print_stats(registry.persons_count, start, timems());
+
+	fprintf(stderr, "\n\nCLEANUP\n");
+	start = timems();
+	registry_free();
+	print_stats(registry.persons_count, start, timems());
+	return 0;
+}
+
+// ----------------------------------------------------------------------------
+// TESTING
+
+int main(int argc, char **argv) {
+	config_set_boolean("registry", "enabled", 1);
+
+	//debug_flags = 0xFFFFFFFF;
+	test1(argc, argv);
+	exit(0);
+
+	(void)argc;
+	(void)argv;
+
+
+	PERSON *p1, *p2;
+
+	fprintf(stderr, "\n\nINITIALIZATION\n");
+
+	registry_init();
+
+	int i = 2;
+
+	fprintf(stderr, "\n\nADDING ENTRY\n");
+	p1 = registry_request_access("2c95abd0-1542-11e6-8c66-00508db7e9c9", "7c173980-145c-11e6-b86f-00508db7e9c1", "http://localhost:19999/", "test", time(NULL));
+
+	if(0)
+	while(i--) {
+#ifdef REGISTRY_STDOUT_DUMP
+		fprintf(stderr, "\n\nADDING ENTRY\n");
+#endif /* REGISTRY_STDOUT_DUMP */
+		p1 = registry_request_access(NULL, "7c173980-145c-11e6-b86f-00508db7e9c1", "http://localhost:19999/", "test", time(NULL));
+
+#ifdef REGISTRY_STDOUT_DUMP
+		fprintf(stderr, "\n\nADDING ANOTHER URL\n");
+#endif /* REGISTRY_STDOUT_DUMP */
+		p1 = registry_request_access(p1->guid, "7c173980-145c-11e6-b86f-00508db7e9c1", "http://127.0.0.1:19999/", "test", time(NULL));
+
+#ifdef REGISTRY_STDOUT_DUMP
+		fprintf(stderr, "\n\nADDING ANOTHER URL\n");
+#endif /* REGISTRY_STDOUT_DUMP */
+		p1 = registry_request_access(p1->guid, "7c173980-145c-11e6-b86f-00508db7e9c1", "http://my.server:19999/", "test", time(NULL));
+
+#ifdef REGISTRY_STDOUT_DUMP
+		fprintf(stderr, "\n\nADDING ANOTHER MACHINE\n");
+#endif /* REGISTRY_STDOUT_DUMP */
+		p1 = registry_request_access(p1->guid, "7c173980-145c-11e6-b86f-00508db7e9c1", "http://my.server:19999/", "test", time(NULL));
+
+#ifdef REGISTRY_STDOUT_DUMP
+		fprintf(stderr, "\n\nADDING ANOTHER PERSON\n");
+#endif /* REGISTRY_STDOUT_DUMP */
+		p2 = registry_request_access(NULL, "7c173980-145c-11e6-b86f-00508db7e9c3", "http://localhost:19999/", "test", time(NULL));
+
+#ifdef REGISTRY_STDOUT_DUMP
+		fprintf(stderr, "\n\nADDING ANOTHER MACHINE\n");
+#endif /* REGISTRY_STDOUT_DUMP */
+		p2 = registry_request_access(p2->guid, "7c173980-145c-11e6-b86f-00508db7e9c3", "http://localhost:19999/", "test", time(NULL));
+	}
+
+	fprintf(stderr, "\n\nSAVE\n");
+	registry_save();
+
+	fprintf(stderr, "\n\nCLEANUP\n");
+	registry_free();
+	return 0;
+}
diff --git a/tests/profile/benchmark-value-pairs.c b/tests/profile/benchmark-value-pairs.c
new file mode 100644
index 0000000..ae4f53c
--- /dev/null
+++ b/tests/profile/benchmark-value-pairs.c
@@ -0,0 +1,623 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+
+#include "config.h"
+#include "libnetdata/libnetdata.h"
+
+#ifdef simple_hash
+#undef simple_hash
+#endif
+
+void netdata_cleanup_and_exit(int ret) {
+    exit(ret);
+}
+
+#define simple_hash(name) ({                                         \
+    register unsigned char *__hash_source = (unsigned char *)(name); \
+    register uint32_t __hash_value = 0x811c9dc5;                     \
+    while (*__hash_source) {                                         \
+        __hash_value *= 16777619;                                    \
+        __hash_value ^= (uint32_t) *__hash_source++;                 \
+    }                                                                \
+    __hash_value;                                                    \
+})
+
+static inline uint32_t simple_hash2(const char *name) {
+    register unsigned char *s = (unsigned char *)name;
+    register uint32_t hval = 0x811c9dc5;
+    while (*s) {
+        hval *= 16777619;
+        hval ^= (uint32_t) *s++;
+    }
+    return hval;
+}
+
+static inline unsigned long long fast_strtoull(const char *s) {
+  register unsigned long long n = 0;
+  register char c;
+  for(c = *s; c >= '0' && c <= '9' ; c = *(++s)) {
+    n *= 10;
+    n += c - '0';
+    // n = (n << 1) + (n << 3) + (c - '0');
+  }
+  return n;
+}
+
+static uint32_t cache_hash = 0;
+static uint32_t rss_hash = 0;
+static uint32_t rss_huge_hash = 0;
+static uint32_t mapped_file_hash = 0;
+static uint32_t writeback_hash = 0;
+static uint32_t dirty_hash = 0;
+static uint32_t swap_hash = 0;
+static uint32_t pgpgin_hash = 0;
+static uint32_t pgpgout_hash = 0;
+static uint32_t pgfault_hash = 0;
+static uint32_t pgmajfault_hash = 0;
+static uint32_t inactive_anon_hash = 0;
+static uint32_t active_anon_hash = 0;
+static uint32_t inactive_file_hash = 0;
+static uint32_t active_file_hash = 0;
+static uint32_t unevictable_hash = 0;
+static uint32_t hierarchical_memory_limit_hash = 0;
+static uint32_t total_cache_hash = 0;
+static uint32_t total_rss_hash = 0;
+static uint32_t total_rss_huge_hash = 0;
+static uint32_t total_mapped_file_hash = 0;
+static uint32_t total_writeback_hash = 0;
+static uint32_t total_dirty_hash = 0;
+static uint32_t total_swap_hash = 0;
+static uint32_t total_pgpgin_hash = 0;
+static uint32_t total_pgpgout_hash = 0;
+static uint32_t total_pgfault_hash = 0;
+static uint32_t total_pgmajfault_hash = 0;
+static uint32_t total_inactive_anon_hash = 0;
+static uint32_t total_active_anon_hash = 0;
+static uint32_t total_inactive_file_hash = 0;
+static uint32_t total_active_file_hash = 0;
+static uint32_t total_unevictable_hash = 0;
+
+unsigned long long values1[50] = { 0 };
+unsigned long long values2[50] = { 0 };
+unsigned long long values3[50] = { 0 };
+unsigned long long values4[50] = { 0 };
+unsigned long long values5[50] = { 0 };
+unsigned long long values6[50] = { 0 };
+unsigned long long values7[50] = { 0 };
+unsigned long long values8[50] = { 0 };
+unsigned long long values9[50] = { 0 };
+
+struct pair {
+    const char *name;
+    const char *value;
+    uint32_t hash;
+    unsigned long long *collected8;
+    unsigned long long *collected9;
+} pairs[] = {
+        { "cache",                      "12345678901234", 0, &values8[0]  ,&values9[0] },
+        { "rss",                        "23456789012345", 0, &values8[1]  ,&values9[1] },
+        { "rss_huge",                   "34567890123456", 0, &values8[2]  ,&values9[2] },
+        { "mapped_file",                "45678901234567", 0, &values8[3]  ,&values9[3] },
+        { "writeback",                  "56789012345678", 0, &values8[4]  ,&values9[4] },
+        { "dirty",                      "67890123456789", 0, &values8[5]  ,&values9[5] },
+        { "swap",                       "78901234567890", 0, &values8[6]  ,&values9[6] },
+        { "pgpgin",                     "89012345678901", 0, &values8[7]  ,&values9[7] },
+        { "pgpgout",                    "90123456789012", 0, &values8[8]  ,&values9[8] },
+        { "pgfault",                    "10345678901234", 0, &values8[9]  ,&values9[9] },
+        { "pgmajfault",                 "11456789012345", 0, &values8[10] ,&values9[10] },
+        { "inactive_anon",              "12000000000000", 0, &values8[11] ,&values9[11] },
+        { "active_anon",                "13345678901234", 0, &values8[12] ,&values9[12] },
+        { "inactive_file",              "14345678901234", 0, &values8[13] ,&values9[13] },
+        { "active_file",                "15345678901234", 0, &values8[14] ,&values9[14] },
+        { "unevictable",                "16345678901234", 0, &values8[15] ,&values9[15] },
+        { "hierarchical_memory_limit",  "17345678901234", 0, &values8[16] ,&values9[16] },
+        { "total_cache",                "18345678901234", 0, &values8[17] ,&values9[17] },
+        { "total_rss",                  "19345678901234", 0, &values8[18] ,&values9[18] },
+        { "total_rss_huge",             "20345678901234", 0, &values8[19] ,&values9[19] },
+        { "total_mapped_file",          "21345678901234", 0, &values8[20] ,&values9[20] },
+        { "total_writeback",            "22345678901234", 0, &values8[21] ,&values9[21] },
+        { "total_dirty",                "23000000000000", 0, &values8[22] ,&values9[22] },
+        { "total_swap",                 "24345678901234", 0, &values8[23] ,&values9[23] },
+        { "total_pgpgin",               "25345678901234", 0, &values8[24] ,&values9[24] },
+        { "total_pgpgout",              "26345678901234", 0, &values8[25] ,&values9[25] },
+        { "total_pgfault",              "27345678901234", 0, &values8[26] ,&values9[26] },
+        { "total_pgmajfault",           "28345678901234", 0, &values8[27] ,&values9[27] },
+        { "total_inactive_anon",        "29345678901234", 0, &values8[28] ,&values9[28] },
+        { "total_active_anon",          "30345678901234", 0, &values8[29] ,&values9[29] },
+        { "total_inactive_file",        "31345678901234", 0, &values8[30] ,&values9[30] },
+        { "total_active_file",          "32345678901234", 0, &values8[31] ,&values9[31] },
+        { "total_unevictable",          "33345678901234", 0, &values8[32] ,&values9[32] },
+        { NULL,                         NULL            , 0, NULL         ,NULL         }
+};
+
+// simple system strcmp()
+void test1() {
+  int i;
+  for(i = 0; pairs[i].name ; i++) {
+    const char *s = pairs[i].name;
+    const char *v = pairs[i].value;
+
+    if(unlikely(!strcmp(s, "cache")))
+      values1[i] = strtoull(v, NULL, 10);
+
+    else if(unlikely(!strcmp(s, "rss")))
+      values1[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "rss_huge")))
+      values1[i] = strtoull(v, NULL, 10);
+  
+    else if(unlikely(!strcmp(s, "mapped_file")))
+      values1[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "writeback")))
+      values1[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "dirty")))
+      values1[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "swap")))
+      values1[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "pgpgin")))
+      values1[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "pgpgout")))
+      values1[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "pgfault")))
+      values1[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(!strcmp(s, "pgmajfault")))
+      values1[i] = strtoull(v, NULL, 10);
+  }
+}
+
+// inline simple_hash() with system strtoull()
+void test2() {
+    int i;
+    for(i = 0; pairs[i].name ; i++) {
+        const char *s = pairs[i].name;
+        const char *v = pairs[i].value;
+
+    uint32_t hash = simple_hash2(s);
+
+    if(unlikely(hash == cache_hash && !strcmp(s, "cache")))
+      values2[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == rss_hash && !strcmp(s, "rss")))
+      values2[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == rss_huge_hash && !strcmp(s, "rss_huge")))
+      values2[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == mapped_file_hash && !strcmp(s, "mapped_file")))
+      values2[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == writeback_hash && !strcmp(s, "writeback")))
+      values2[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == dirty_hash && !strcmp(s, "dirty")))
+      values2[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == swap_hash && !strcmp(s, "swap")))
+      values2[i] = strtoull(v, NULL, 10);
+  
+    else if(unlikely(hash == pgpgin_hash && !strcmp(s, "pgpgin")))
+      values2[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == pgpgout_hash && !strcmp(s, "pgpgout")))
+      values2[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == pgfault_hash && !strcmp(s, "pgfault")))
+      values2[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == pgmajfault_hash && !strcmp(s, "pgmajfault")))
+      values2[i] = strtoull(v, NULL, 10);
+  }
+}
+
+// statement expression simple_hash(), system strtoull()
+void test3() {
+    int i;
+    for(i = 0; pairs[i].name ; i++) {
+        const char *s = pairs[i].name;
+        const char *v = pairs[i].value;
+
+    uint32_t hash = simple_hash(s);
+
+    if(unlikely(hash == cache_hash && !strcmp(s, "cache")))
+      values3[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == rss_hash && !strcmp(s, "rss")))
+      values3[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == rss_huge_hash && !strcmp(s, "rss_huge")))
+      values3[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == mapped_file_hash && !strcmp(s, "mapped_file")))
+      values3[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == writeback_hash && !strcmp(s, "writeback")))
+      values3[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == dirty_hash && !strcmp(s, "dirty")))
+      values3[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == swap_hash && !strcmp(s, "swap")))
+      values3[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == pgpgin_hash && !strcmp(s, "pgpgin")))
+      values3[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == pgpgout_hash && !strcmp(s, "pgpgout")))
+      values3[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == pgfault_hash && !strcmp(s, "pgfault")))
+      values3[i] = strtoull(v, NULL, 10);
+    
+    else if(unlikely(hash == pgmajfault_hash && !strcmp(s, "pgmajfault")))
+      values3[i] = strtoull(v, NULL, 10);
+  }
+}
+
+
+// inline simple_hash(), if-continue checks
+void test4() {
+    int i;
+    for(i = 0; pairs[i].name ; i++) {
+        const char *s = pairs[i].name;
+        const char *v = pairs[i].value;
+
+    uint32_t hash = simple_hash2(s);
+
+    if(unlikely(hash == cache_hash && !strcmp(s, "cache"))) {
+      values4[i] = strtoull(v, NULL, 0);
+      continue;
+    }
+
+    if(unlikely(hash == rss_hash && !strcmp(s, "rss"))) {
+      values4[i] = strtoull(v, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == rss_huge_hash && !strcmp(s, "rss_huge"))) {
+      values4[i] = strtoull(v, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == mapped_file_hash && !strcmp(s, "mapped_file"))) {
+      values4[i] = strtoull(v, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == writeback_hash && !strcmp(s, "writeback"))) {
+      values4[i] = strtoull(v, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == dirty_hash && !strcmp(s, "dirty"))) {
+      values4[i] = strtoull(v, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == swap_hash && !strcmp(s, "swap"))) {
+      values4[i] = strtoull(v, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == pgpgin_hash && !strcmp(s, "pgpgin"))) {
+      values4[i] = strtoull(v, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == pgpgout_hash && !strcmp(s, "pgpgout"))) {
+      values4[i] = strtoull(v, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == pgfault_hash && !strcmp(s, "pgfault"))) {
+      values4[i] = strtoull(v, NULL, 0);
+      continue;
+    }
+    
+    if(unlikely(hash == pgmajfault_hash && !strcmp(s, "pgmajfault"))) {
+      values4[i] = strtoull(v, NULL, 0);
+      continue;
+    }
+  }
+}
+
+// inline simple_hash(), if-else-if-else-if (netdata default)
+void test5() {
+    int i;
+    for(i = 0; pairs[i].name ; i++) {
+        const char *s = pairs[i].name;
+        const char *v = pairs[i].value;
+
+    uint32_t hash = simple_hash2(s);
+
+    if(unlikely(hash == cache_hash && !strcmp(s, "cache")))
+      values5[i] = fast_strtoull(v);
+    
+    else if(unlikely(hash == rss_hash && !strcmp(s, "rss")))
+      values5[i] = fast_strtoull(v);
+    
+    else if(unlikely(hash == rss_huge_hash && !strcmp(s, "rss_huge")))
+      values5[i] = fast_strtoull(v);
+    
+    else if(unlikely(hash == mapped_file_hash && !strcmp(s, "mapped_file")))
+      values5[i] = fast_strtoull(v);
+    
+    else if(unlikely(hash == writeback_hash && !strcmp(s, "writeback")))
+      values5[i] = fast_strtoull(v);
+    
+    else if(unlikely(hash == dirty_hash && !strcmp(s, "dirty")))
+      values5[i] = fast_strtoull(v);
+    
+    else if(unlikely(hash == swap_hash && !strcmp(s, "swap")))
+      values5[i] = fast_strtoull(v);
+  
+    else if(unlikely(hash == pgpgin_hash && !strcmp(s, "pgpgin")))
+      values5[i] = fast_strtoull(v);
+    
+    else if(unlikely(hash == pgpgout_hash && !strcmp(s, "pgpgout")))
+      values5[i] = fast_strtoull(v);
+    
+    else if(unlikely(hash == pgfault_hash && !strcmp(s, "pgfault")))
+      values5[i] = fast_strtoull(v);
+    
+    else if(unlikely(hash == pgmajfault_hash && !strcmp(s, "pgmajfault")))
+      values5[i] = fast_strtoull(v);
+  }
+}
+
+// ----------------------------------------------------------------------------
+
+void arl_strtoull(const char *name, uint32_t hash, const char *value, void *dst) {
+    (void)name;
+    (void)hash;
+
+    register unsigned long long *d = dst;
+    *d = strtoull(value, NULL, 10);
+    // fprintf(stderr, "name '%s' with hash %u and value '%s' is %llu\n", name, hash, value, *d);
+}
+
+void test6() {
+    static ARL_BASE *base = NULL;
+
+    if(unlikely(!base)) {
+        base = arl_create("test6", arl_strtoull, 60);
+        arl_expect_custom(base, "cache",       NULL, &values6[0]);
+        arl_expect_custom(base, "rss",         NULL, &values6[1]);
+        arl_expect_custom(base, "rss_huge",    NULL, &values6[2]);
+        arl_expect_custom(base, "mapped_file", NULL, &values6[3]);
+        arl_expect_custom(base, "writeback",   NULL, &values6[4]);
+        arl_expect_custom(base, "dirty",       NULL, &values6[5]);
+        arl_expect_custom(base, "swap",        NULL, &values6[6]);
+        arl_expect_custom(base, "pgpgin",      NULL, &values6[7]);
+        arl_expect_custom(base, "pgpgout",     NULL, &values6[8]);
+        arl_expect_custom(base, "pgfault",     NULL, &values6[9]);
+        arl_expect_custom(base, "pgmajfault",  NULL, &values6[10]);
+    }
+
+    arl_begin(base);
+
+    int i;
+    for(i = 0; pairs[i].name ; i++)
+        if(arl_check(base, pairs[i].name, pairs[i].value)) break;
+}
+
+void arl_str2ull(const char *name, uint32_t hash, const char *value, void *dst) {
+    (void)name;
+    (void)hash;
+
+    register unsigned long long *d = dst;
+    *d = str2ull(value);
+    // fprintf(stderr, "name '%s' with hash %u and value '%s' is %llu\n", name, hash, value, *d);
+}
+
+void test7() {
+    static ARL_BASE *base = NULL;
+
+    if(unlikely(!base)) {
+        base = arl_create("test7", arl_str2ull, 60);
+        arl_expect_custom(base, "cache",       NULL, &values7[0]);
+        arl_expect_custom(base, "rss",         NULL, &values7[1]);
+        arl_expect_custom(base, "rss_huge",    NULL, &values7[2]);
+        arl_expect_custom(base, "mapped_file", NULL, &values7[3]);
+        arl_expect_custom(base, "writeback",   NULL, &values7[4]);
+        arl_expect_custom(base, "dirty",       NULL, &values7[5]);
+        arl_expect_custom(base, "swap",        NULL, &values7[6]);
+        arl_expect_custom(base, "pgpgin",      NULL, &values7[7]);
+        arl_expect_custom(base, "pgpgout",     NULL, &values7[8]);
+        arl_expect_custom(base, "pgfault",     NULL, &values7[9]);
+        arl_expect_custom(base, "pgmajfault",  NULL, &values7[10]);
+    }
+
+    arl_begin(base);
+
+    int i;
+    for(i = 0; pairs[i].name ; i++)
+        if(arl_check(base, pairs[i].name, pairs[i].value)) break;
+}
+
+void test8() {
+    int i;
+    for(i = 0; pairs[i].name; i++) {
+        uint32_t hash = simple_hash(pairs[i].name);
+
+        int j;
+        for(j = 0; pairs[j].name; j++) {
+            if(hash == pairs[j].hash && !strcmp(pairs[i].name, pairs[j].name)) {
+                *pairs[j].collected8 = strtoull(pairs[i].value, NULL, 10);
+                break;
+            }
+        }
+    }
+}
+
+void test9() {
+    int i;
+    for(i = 0; pairs[i].name; i++) {
+        uint32_t hash = simple_hash(pairs[i].name);
+
+        int j;
+        for(j = 0; pairs[j].name; j++) {
+            if(hash == pairs[j].hash && !strcmp(pairs[i].name, pairs[j].name)) {
+                *pairs[j].collected9 = str2ull(pairs[i].value);
+                break;
+            }
+        }
+    }
+}
+
+// ----------------------------------------------------------------------------
+
+/*
+// ==============
+// --- Poor man cycle counting.
+static unsigned long tsc;
+
+static void begin_tsc(void)
+{
+  unsigned long a, d;
+  asm volatile ("cpuid\nrdtsc" : "=a" (a), "=d" (d) : "0" (0) : "ebx", "ecx");
+  tsc = ((unsigned long)d << 32) | (unsigned long)a;
+}
+
+static unsigned long end_tsc(void)
+{
+  unsigned long a, d;
+  asm volatile ("rdtscp" : "=a" (a), "=d" (d) : : "ecx");
+  return (((unsigned long)d << 32) | (unsigned long)a) - tsc;
+}
+// ===============
+*/
+
+static unsigned long long clk;
+
+static void begin_clock() {
+    struct timeval tv;
+    if(unlikely(gettimeofday(&tv, NULL) == -1))
+        return;
+    clk = tv.tv_sec  * 1000000 + tv.tv_usec;
+}
+
+static unsigned long long end_clock() {
+    struct timeval tv;
+    if(unlikely(gettimeofday(&tv, NULL) == -1))
+        return -1;
+    return clk = tv.tv_sec  * 1000000 + tv.tv_usec - clk;
+}
+
+int main(void)
+{
+    {
+        int i;
+        for(i = 0; pairs[i].name; i++)
+            pairs[i].hash = simple_hash(pairs[i].name);
+    }
+
+    cache_hash = simple_hash("cache");
+    rss_hash = simple_hash("rss");
+    rss_huge_hash = simple_hash("rss_huge");
+    mapped_file_hash = simple_hash("mapped_file");
+    writeback_hash = simple_hash("writeback");
+    dirty_hash = simple_hash("dirty");
+    swap_hash = simple_hash("swap");
+    pgpgin_hash = simple_hash("pgpgin");
+    pgpgout_hash = simple_hash("pgpgout");
+    pgfault_hash = simple_hash("pgfault");
+    pgmajfault_hash = simple_hash("pgmajfault");
+    inactive_anon_hash = simple_hash("inactive_anon");
+    active_anon_hash = simple_hash("active_anon");
+    inactive_file_hash = simple_hash("inactive_file");
+    active_file_hash = simple_hash("active_file");
+    unevictable_hash = simple_hash("unevictable");
+    hierarchical_memory_limit_hash = simple_hash("hierarchical_memory_limit");
+    total_cache_hash = simple_hash("total_cache");
+    total_rss_hash = simple_hash("total_rss");
+    total_rss_huge_hash = simple_hash("total_rss_huge");
+    total_mapped_file_hash = simple_hash("total_mapped_file");
+    total_writeback_hash = simple_hash("total_writeback");
+    total_dirty_hash = simple_hash("total_dirty");
+    total_swap_hash = simple_hash("total_swap");
+    total_pgpgin_hash = simple_hash("total_pgpgin");
+    total_pgpgout_hash = simple_hash("total_pgpgout");
+    total_pgfault_hash = simple_hash("total_pgfault");
+    total_pgmajfault_hash = simple_hash("total_pgmajfault");
+    total_inactive_anon_hash = simple_hash("total_inactive_anon");
+    total_active_anon_hash = simple_hash("total_active_anon");
+    total_inactive_file_hash = simple_hash("total_inactive_file");
+    total_active_file_hash = simple_hash("total_active_file");
+    total_unevictable_hash = simple_hash("total_unevictable");
+
+    // cache functions
+    (void)simple_hash2("hello world");
+    (void)strcmp("1", "2");
+    (void)strtoull("123", NULL, 0);
+
+  unsigned long i, c1 = 0, c2 = 0, c3 = 0, c4 = 0, c5 = 0, c6 = 0, c7 = 0, c8 = 0, c9 = 0;
+  unsigned long max = 1000000;
+
+  begin_clock();
+  for(i = 0; i <= max ;i++) test1();
+  c1 = end_clock();
+
+  begin_clock();
+  for(i = 0; i <= max ;i++) test2();
+  c2 = end_clock();
+    
+  begin_clock();
+  for(i = 0; i <= max ;i++) test3();
+  c3 = end_clock();
+
+  begin_clock();
+  for(i = 0; i <= max ;i++) test4();
+  c4 = end_clock();
+
+  begin_clock();
+  for(i = 0; i <= max ;i++) test5();
+  c5 = end_clock();
+
+    begin_clock();
+    for(i = 0; i <= max ;i++) test6();
+    c6 = end_clock();
+
+    begin_clock();
+    for(i = 0; i <= max ;i++) test7();
+    c7 = end_clock();
+
+    begin_clock();
+    for(i = 0; i <= max ;i++) test8();
+    c8 = end_clock();
+
+    begin_clock();
+    for(i = 0; i <= max ;i++) test9();
+    c9 = end_clock();
+
+    for(i = 0; i < 11 ; i++)
+        printf("value %lu: %llu %llu %llu %llu %llu %llu %llu %llu %llu\n", i, values1[i], values2[i], values3[i], values4[i], values5[i], values6[i], values7[i], values8[i], values9[i]);
+  
+  printf("\n\nRESULTS\n");
+  printf("test1() [1] in %lu usecs: simple system strcmp().\n"
+         "test2() [4] in %lu usecs: inline simple_hash() with system strtoull().\n"
+         "test3() [5] in %lu usecs: statement expression simple_hash(), system strtoull().\n"
+         "test4() [6] in %lu usecs: inline simple_hash(), if-continue checks.\n"
+         "test5() [7] in %lu usecs: inline simple_hash(), if-else-if-else-if (netdata default prior to ARL).\n"
+         "test6() [8] in %lu usecs: adaptive re-sortable array with strtoull() (wow!)\n"
+         "test7() [9] in %lu usecs: adaptive re-sortable array with str2ull() (wow!)\n"
+         "test8() [2] in %lu usecs: nested loop with strtoull()\n"
+         "test9() [3] in %lu usecs: nested loop with str2ull()\n"
+         , c1
+         , c2
+         , c3
+         , c4
+         , c5
+         , c6
+         , c7
+         , c8
+         , c9
+         );
+
+  return 0;
+}
diff --git a/tests/profile/statsd-stress.c b/tests/profile/statsd-stress.c
new file mode 100644
index 0000000..435d58d
--- /dev/null
+++ b/tests/profile/statsd-stress.c
@@ -0,0 +1,151 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+#include <stdlib.h>
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <unistd.h>
+#include <string.h>
+#include <time.h>
+#include <pthread.h>
+
+void diep(char *s)
+{
+	perror(s);
+	exit(1);
+}
+
+size_t run_threads = 1;
+size_t metrics = 1024;
+
+#define SERVER_IP "127.0.0.1"
+#define PORT 8125
+
+size_t myrand(size_t max) {
+	size_t loops = max / RAND_MAX;
+	size_t i;
+
+	size_t ret = rand();
+	for(i = 0; i < loops ;i++)
+		ret += rand();
+
+	return ret % max;
+}
+
+struct thread_data {
+	size_t id;
+	struct sockaddr_in *si_other;
+	int slen;
+	size_t counter;
+};
+
+static void *report_thread(void *__data) {
+	struct thread_data *data = (struct thread_data *)__data;
+
+	size_t last = 0;
+	for (;;) {
+		size_t i;
+		size_t total = 0;
+		for(i = 0; i < run_threads ;i++)
+			total += data[i].counter;
+
+		printf("%zu metrics/s\n", total-last);
+		last = total;
+
+		sleep(1);
+		printf("\033[F\033[J");
+	}
+
+	return NULL;
+}
+
+char *types[] = {"g", "c", "m", "ms", "h", "s", NULL};
+// char *types[] = {"g", "c", "C", "h", "ms", NULL}; // brubeck compatible
+
+static void *spam_thread(void *__data) {
+	struct thread_data *data = (struct thread_data *)__data;
+
+	int s;
+	char packet[1024];
+
+	if ((s = socket(AF_INET, SOCK_DGRAM, 0))==-1)
+		diep("socket");
+
+	char **packets = malloc(sizeof(char *) * metrics);
+	size_t i, *lengths = malloc(sizeof(size_t) * metrics);
+	size_t t;
+
+	for(i = 0, t = 0; i < metrics ;i++, t++) {
+		if(!types[t]) t = 0;
+		char *type = types[t];
+
+		lengths[i] = sprintf(packet, "stress.%s.t%zu.m%zu:%zu|%s", type, data->id, i, myrand(metrics), type);
+		packets[i] = strdup(packet);
+		// printf("packet %zu, of length %zu: '%s'\n", i, lengths[i], packets[i]);
+	}
+	//printf("\n");
+
+	for (;;) {
+		for(i = 0; i < metrics ;i++) {
+			if (sendto(s, packets[i], lengths[i], 0, (void *)data->si_other, data->slen) < 0) {
+				printf("C ==> DROPPED\n");
+				return NULL;
+			}
+			data->counter++;
+		}
+	}
+
+	free(packets);
+	free(lengths);
+	close(s);
+	return NULL;
+}
+
+int main(int argc, char *argv[])
+{
+	if (argc != 5) {
+		fprintf(stderr, "Usage: '%s THREADS METRICS IP PORT'\n", argv[0]);
+		exit(-1);
+	}
+
+	run_threads = atoi(argv[1]);
+	metrics = atoi(argv[2]);
+	char *ip = argv[3];
+	int port = atoi(argv[4]);
+
+	struct thread_data data[run_threads];
+	struct sockaddr_in si_other;
+	pthread_t threads[run_threads], report;
+	size_t i;
+
+	srand(time(NULL));
+
+	memset(&si_other, 0, sizeof(si_other));
+	si_other.sin_family = AF_INET;
+	si_other.sin_port = htons(port);
+	if (inet_aton(ip, &si_other.sin_addr)==0) {
+		fprintf(stderr, "inet_aton() of ip '%s' failed\n", ip);
+		exit(1);
+	}
+
+	for (i = 0; i < run_threads; ++i) {
+		data[i].id       = i;
+		data[i].si_other = &si_other;
+		data[i].slen     = sizeof(si_other);
+		data[i].counter  = 0;
+		pthread_create(&threads[i], NULL, spam_thread, &data[i]);
+	}
+
+	printf("\n");
+	printf("THREADS     : %zu\n", run_threads);
+	printf("METRICS     : %zu\n", metrics);
+	printf("DESTINATION : %s:%d\n", ip, port);
+	printf("\n");
+	pthread_create(&report, NULL, report_thread, &data);
+
+	for (i =0; i < run_threads; ++i)
+		pthread_join(threads[i], NULL);
+
+	return 0;
+}
diff --git a/tests/profile/test-eval.c b/tests/profile/test-eval.c
new file mode 100644
index 0000000..3c46316
--- /dev/null
+++ b/tests/profile/test-eval.c
@@ -0,0 +1,289 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+
+/*
+ * 1. build netdata (as normally)
+ * 2. cd profile/
+ * 3. compile with:
+ *    gcc -O1 -ggdb -Wall -Wextra -I ../src/ -I ../ -o test-eval test-eval.c ../src/log.o ../src/eval.o ../src/common.o ../src/clocks.o ../src/web_buffer.o ../src/storage_number.o -pthread -lm
+ */
+
+#include "config.h"
+#include "libnetdata/libnetdata.h"
+#include "libnetdata/required_dummies.h"
+#include "database/rrdcalc.h"
+
+/*
+void indent(int level, int show) {
+	int i = level;
+	while(i--) printf(" |  ");
+	if(show) printf(" \\_ ");
+	else printf(" \\_  ");
+}
+
+void print_node(EVAL_NODE *op, int level);
+
+void print_value(EVAL_VALUE *v, int level) {
+	indent(level, 0);
+
+	switch(v->type) {
+		case EVAL_VALUE_INVALID:
+			printf("value (NOP)\n");
+			break;
+
+		case EVAL_VALUE_NUMBER:
+			printf("value %Lf (NUMBER)\n", v->number);
+			break;
+
+		case EVAL_VALUE_EXPRESSION:
+			printf("value (SUB-EXPRESSION)\n");
+			print_node(v->expression, level+1);
+			break;
+
+		default:
+			printf("value (INVALID type %d)\n", v->type);
+			break;
+
+	}
+}
+
+void print_node(EVAL_NODE *op, int level) {
+
+//	if(op->operator != EVAL_OPERATOR_NOP) {
+		indent(level, 1);
+		if(op->operator) printf("%c (node %d, precedence: %d)\n", op->operator, op->id, op->precedence);
+		else printf("NOP (node %d, precedence: %d)\n", op->id, op->precedence);
+//	}
+
+	int i = op->count;
+	while(i--) print_value(&op->ops[i], level + 1);
+}
+
+NETDATA_DOUBLE evaluate(EVAL_NODE *op, int depth);
+
+NETDATA_DOUBLE evaluate_value(EVAL_VALUE *v, int depth) {
+	switch(v->type) {
+		case EVAL_VALUE_NUMBER:
+			return v->number;
+
+		case EVAL_VALUE_EXPRESSION:
+			return evaluate(v->expression, depth);
+
+		default:
+			fatal("I don't know how to handle EVAL_VALUE type %d", v->type);
+	}
+}
+
+void print_depth(int depth) {
+	static int count = 0;
+
+	printf("%d. ", ++count);
+	while(depth--) printf("    ");
+}
+
+NETDATA_DOUBLE evaluate(EVAL_NODE *op, int depth) {
+	NETDATA_DOUBLE n1, n2, r;
+
+	switch(op->operator) {
+		case EVAL_OPERATOR_SIGN_PLUS:
+			r = evaluate_value(&op->ops[0], depth);
+			break;
+
+		case EVAL_OPERATOR_SIGN_MINUS:
+			r = -evaluate_value(&op->ops[0], depth);
+			break;
+
+		case EVAL_OPERATOR_PLUS:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0], depth);
+			n2 = evaluate_value(&op->ops[1], depth);
+			r = n1 + n2;
+			print_depth(depth);
+			printf("%Lf = %Lf + %Lf\n", r, n1, n2);
+			break;
+
+		case EVAL_OPERATOR_MINUS:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0], depth);
+			n2 = evaluate_value(&op->ops[1], depth);
+			r = n1 - n2;
+			print_depth(depth);
+			printf("%Lf = %Lf - %Lf\n", r, n1, n2);
+			break;
+
+		case EVAL_OPERATOR_MULTIPLY:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0], depth);
+			n2 = evaluate_value(&op->ops[1], depth);
+			r = n1 * n2;
+			print_depth(depth);
+			printf("%Lf = %Lf * %Lf\n", r, n1, n2);
+			break;
+
+		case EVAL_OPERATOR_DIVIDE:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0], depth);
+			n2 = evaluate_value(&op->ops[1], depth);
+			r = n1 / n2;
+			print_depth(depth);
+			printf("%Lf = %Lf / %Lf\n", r, n1, n2);
+			break;
+
+		case EVAL_OPERATOR_NOT:
+			n1 = evaluate_value(&op->ops[0], depth);
+			r = !n1;
+			print_depth(depth);
+			printf("%Lf = NOT %Lf\n", r, n1);
+			break;
+
+		case EVAL_OPERATOR_AND:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0], depth);
+			n2 = evaluate_value(&op->ops[1], depth);
+			r = n1 && n2;
+			print_depth(depth);
+			printf("%Lf = %Lf AND %Lf\n", r, n1, n2);
+			break;
+
+		case EVAL_OPERATOR_OR:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0], depth);
+			n2 = evaluate_value(&op->ops[1], depth);
+			r = n1 || n2;
+			print_depth(depth);
+			printf("%Lf = %Lf OR %Lf\n", r, n1, n2);
+			break;
+
+		case EVAL_OPERATOR_GREATER_THAN_OR_EQUAL:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0], depth);
+			n2 = evaluate_value(&op->ops[1], depth);
+			r = n1 >= n2;
+			print_depth(depth);
+			printf("%Lf = %Lf >= %Lf\n", r, n1, n2);
+			break;
+
+		case EVAL_OPERATOR_LESS_THAN_OR_EQUAL:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0], depth);
+			n2 = evaluate_value(&op->ops[1], depth);
+			r = n1 <= n2;
+			print_depth(depth);
+			printf("%Lf = %Lf <= %Lf\n", r, n1, n2);
+			break;
+
+		case EVAL_OPERATOR_GREATER:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0], depth);
+			n2 = evaluate_value(&op->ops[1], depth);
+			r = n1 > n2;
+			print_depth(depth);
+			printf("%Lf = %Lf > %Lf\n", r, n1, n2);
+			break;
+
+		case EVAL_OPERATOR_LESS:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0], depth);
+			n2 = evaluate_value(&op->ops[1], depth);
+			r = n1 < n2;
+			print_depth(depth);
+			printf("%Lf = %Lf < %Lf\n", r, n1, n2);
+			break;
+
+		case EVAL_OPERATOR_NOT_EQUAL:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0], depth);
+			n2 = evaluate_value(&op->ops[1], depth);
+			r = n1 != n2;
+			print_depth(depth);
+			printf("%Lf = %Lf <> %Lf\n", r, n1, n2);
+			break;
+
+		case EVAL_OPERATOR_EQUAL:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0], depth);
+			n2 = evaluate_value(&op->ops[1], depth);
+			r = n1 == n2;
+			print_depth(depth);
+			printf("%Lf = %Lf == %Lf\n", r, n1, n2);
+			break;
+
+		case EVAL_OPERATOR_EXPRESSION_OPEN:
+			printf("BEGIN SUB-EXPRESSION\n");
+			r = evaluate_value(&op->ops[0], depth + 1);
+			printf("END SUB-EXPRESSION\n");
+			break;
+
+		case EVAL_OPERATOR_NOP:
+		case EVAL_OPERATOR_VALUE:
+			r = evaluate_value(&op->ops[0], depth);
+			break;
+
+		default:
+			error("I don't know how to handle operator '%c'", op->operator);
+			r = 0;
+			break;
+	}
+
+	return r;
+}
+
+
+void print_expression(EVAL_NODE *op, const char *failed_at, int error) {
+	if(op) {
+		printf("expression tree:\n");
+		print_node(op, 0);
+
+		printf("\nevaluation steps:\n");
+		evaluate(op, 0);
+		
+		int error;
+		NETDATA_DOUBLE ret = expression_evaluate(op, &error);
+		printf("\ninternal evaluator:\nSTATUS: %d, RESULT = %Lf\n", error, ret);
+
+		expression_free(op);
+	}
+	else {
+		printf("error: %d, failed_at: '%s'\n", error, (failed_at)?failed_at:"<NONE>");
+	}
+}
+*/
+
+int main(int argc, char **argv) {
+	if(argc != 2) {
+		fprintf(stderr, "I need an expression (enclose it in single-quotes (') as a single parameter)\n");
+		exit(1);
+	}
+
+	const char *failed_at = NULL;
+	int error;
+
+	EVAL_EXPRESSION *exp = expression_parse(argv[1], &failed_at, &error);
+	if(!exp)
+		printf("\nPARSING FAILED\nExpression: '%s'\nParsing stopped at: '%s'\nParsing error code: %d (%s)\n", argv[1], (failed_at)?((*failed_at)?failed_at:"<END OF EXPRESSION>"):"<NONE>", error, expression_strerror(error));
+	
+	else {
+		printf("\nPARSING OK\nExpression: '%s'\nParsed as : '%s'\nParsing error code: %d (%s)\n", argv[1], exp->parsed_as, error, expression_strerror(error));
+
+		if(expression_evaluate(exp)) {
+			printf("\nEvaluates to: %Lf\n\n", exp->result);
+		}
+		else {
+			printf("\nEvaluation failed with code %d and message: %s\n\n", exp->error, buffer_tostring(exp->error_msg));
+		}
+		expression_free(exp);
+	}
+
+	return 0;
+}