Improve multithreaded performance with memory prefetching

src/Makefile

@@ -423,7 +423,7 @@ endif
 ENGINE_NAME=valkey
 SERVER_NAME=$(ENGINE_NAME)-server$(PROG_SUFFIX)
 ENGINE_SENTINEL_NAME=$(ENGINE_NAME)-sentinel$(PROG_SUFFIX)
-ENGINE_SERVER_OBJ=threads_mngr.o adlist.o quicklist.o ae.o anet.o dict.o kvstore.o server.o sds.o zmalloc.o lzf_c.o lzf_d.o pqsort.o zipmap.o sha1.o ziplist.o release.o io_threads.o networking.o util.o object.o db.o replication.o rdb.o t_string.o t_list.o t_set.o t_zset.o t_hash.o config.o aof.o pubsub.o multi.o debug.o sort.o intset.o syncio.o cluster.o cluster_legacy.o cluster_slot_stats.o crc16.o endianconv.o slowlog.o eval.o bio.o rio.o rand.o memtest.o syscheck.o crcspeed.o crccombine.o crc64.o bitops.o sentinel.o notify.o setproctitle.o blocked.o hyperloglog.o latency.o sparkline.o valkey-check-rdb.o valkey-check-aof.o geo.o lazyfree.o module.o evict.o expire.o geohash.o geohash_helper.o childinfo.o defrag.o siphash.o rax.o t_stream.o listpack.o localtime.o lolwut.o lolwut5.o lolwut6.o acl.o tracking.o socket.o tls.o sha256.o timeout.o setcpuaffinity.o monotonic.o mt19937-64.o resp_parser.o call_reply.o script_lua.o script.o functions.o function_lua.o commands.o strl.o connection.o unix.o logreqres.o
+ENGINE_SERVER_OBJ=threads_mngr.o adlist.o quicklist.o ae.o anet.o dict.o kvstore.o server.o sds.o zmalloc.o lzf_c.o lzf_d.o pqsort.o zipmap.o sha1.o ziplist.o release.o memory_prefetch.o io_threads.o networking.o util.o object.o db.o replication.o rdb.o t_string.o t_list.o t_set.o t_zset.o t_hash.o config.o aof.o pubsub.o multi.o debug.o sort.o intset.o syncio.o cluster.o cluster_legacy.o cluster_slot_stats.o crc16.o endianconv.o slowlog.o eval.o bio.o rio.o rand.o memtest.o syscheck.o crcspeed.o crccombine.o crc64.o bitops.o sentinel.o notify.o setproctitle.o blocked.o hyperloglog.o latency.o sparkline.o valkey-check-rdb.o valkey-check-aof.o geo.o lazyfree.o module.o evict.o expire.o geohash.o geohash_helper.o childinfo.o defrag.o siphash.o rax.o t_stream.o listpack.o localtime.o lolwut.o lolwut5.o lolwut6.o acl.o tracking.o socket.o tls.o sha256.o timeout.o setcpuaffinity.o monotonic.o mt19937-64.o resp_parser.o call_reply.o script_lua.o script.o functions.o function_lua.o commands.o strl.o connection.o unix.o logreqres.o
 ENGINE_CLI_NAME=$(ENGINE_NAME)-cli$(PROG_SUFFIX)
 ENGINE_CLI_OBJ=anet.o adlist.o dict.o valkey-cli.o zmalloc.o release.o ae.o serverassert.o crcspeed.o crccombine.o crc64.o siphash.o crc16.o monotonic.o cli_common.o mt19937-64.o strl.o cli_commands.o
 ENGINE_BENCHMARK_NAME=$(ENGINE_NAME)-benchmark$(PROG_SUFFIX)

src/config.c

@@ -3164,6 +3164,7 @@ standardConfig static_configs[] = {
     createIntConfig("port", NULL, MODIFIABLE_CONFIG, 0, 65535, server.port, 6379, INTEGER_CONFIG, NULL, updatePort), /* TCP port. */
     createIntConfig("io-threads", NULL, DEBUG_CONFIG | IMMUTABLE_CONFIG, 1, 128, server.io_threads_num, 1, INTEGER_CONFIG, NULL, NULL), /* Single threaded by default */
     createIntConfig("events-per-io-thread", NULL, MODIFIABLE_CONFIG, 0, INT_MAX, server.events_per_io_thread, 2, INTEGER_CONFIG, NULL, NULL),
+    createIntConfig("prefetch-batch-max-size", NULL, MODIFIABLE_CONFIG, 0, 128, server.prefetch_batch_max_size, 16, INTEGER_CONFIG, NULL, NULL),
     createIntConfig("auto-aof-rewrite-percentage", NULL, MODIFIABLE_CONFIG, 0, INT_MAX, server.aof_rewrite_perc, 100, INTEGER_CONFIG, NULL, NULL),
     createIntConfig("cluster-replica-validity-factor", "cluster-slave-validity-factor", MODIFIABLE_CONFIG, 0, INT_MAX, server.cluster_replica_validity_factor, 10, INTEGER_CONFIG, NULL, NULL), /* replica max data age factor. */
     createIntConfig("list-max-listpack-size", "list-max-ziplist-size", MODIFIABLE_CONFIG, INT_MIN, INT_MAX, server.list_max_listpack_size, -2, INTEGER_CONFIG, NULL, NULL),

src/config.h

@@ -348,4 +348,20 @@ void setcpuaffinity(const char *cpulist);
 #endif
 #endif
 
+/* Check for GCC version >= 4.9 */
+#if defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 9))
+#define HAS_BUILTIN_PREFETCH 1
+/* Check for Clang version >= 3.6 */
+#elif defined(__clang__) && (__clang_major__ > 3 || (__clang_major__ == 3 && __clang_minor__ >= 6))
+#define HAS_BUILTIN_PREFETCH 1
+#else
+#define HAS_BUILTIN_PREFETCH 0
+#endif
+
+#if HAS_BUILTIN_PREFETCH
+#define valkey_prefetch(addr) __builtin_prefetch(addr)
+#else
+#define valkey_prefetch(addr) ((void)(addr))
+#endif
+
 #endif

src/dict.c

@@ -48,6 +48,7 @@
 #include "zmalloc.h"
 #include "serverassert.h"
 #include "monotonic.h"
+#include "config.h"
 
 #ifndef static_assert
 #define static_assert(expr, lit) _Static_assert(expr, lit)
@@ -119,7 +120,6 @@ static void _dictExpandIfNeeded(dict *d);
 static void _dictShrinkIfNeeded(dict *d);
 static signed char _dictNextExp(unsigned long size);
 static int _dictInit(dict *d, dictType *type);
-static dictEntry *dictGetNext(const dictEntry *de);
 static dictEntry **dictGetNextRef(dictEntry *de);
 static void dictSetNext(dictEntry *de, dictEntry *next);
 
@@ -962,7 +962,7 @@ double *dictGetDoubleValPtr(dictEntry *de) {
 
 /* Returns the 'next' field of the entry or NULL if the entry doesn't have a
  * 'next' field. */
-static dictEntry *dictGetNext(const dictEntry *de) {
+dictEntry *dictGetNext(const dictEntry *de) {
     if (entryIsKey(de)) return NULL; /* there's no next */
     if (entryIsNoValue(de)) return decodeEntryNoValue(de)->next;
     if (entryIsEmbedded(de)) return decodeEmbeddedEntry(de)->next;

src/dict.h

@@ -229,6 +229,7 @@ void dictInitIterator(dictIterator *iter, dict *d);
 void dictInitSafeIterator(dictIterator *iter, dict *d);
 void dictResetIterator(dictIterator *iter);
 dictEntry *dictNext(dictIterator *iter);
+dictEntry *dictGetNext(const dictEntry *de);
 void dictReleaseIterator(dictIterator *iter);
 dictEntry *dictGetRandomKey(dict *d);
 dictEntry *dictGetFairRandomKey(dict *d);

src/fmtargs.h

@@ -44,9 +44,9 @@
 /* Everything below this line is automatically generated by
  * generate-fmtargs.py. Do not manually edit. */
 
-#define ARG_N(_1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, _18, _19, _20, _21, _22, _23, _24, _25, _26, _27, _28, _29, _30, _31, _32, _33, _34, _35, _36, _37, _38, _39, _40, _41, _42, _43, _44, _45, _46, _47, _48, _49, _50, _51, _52, _53, _54, _55, _56, _57, _58, _59, _60, _61, _62, _63, _64, _65, _66, _67, _68, _69, _70, _71, _72, _73, _74, _75, _76, _77, _78, _79, _80, _81, _82, _83, _84, _85, _86, _87, _88, _89, _90, _91, _92, _93, _94, _95, _96, _97, _98, _99, _100, _101, _102, _103, _104, _105, _106, _107, _108, _109, _110, _111, _112, _113, _114, _115, _116, _117, _118, _119, _120, N, ...) N
+#define ARG_N(_1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, _18, _19, _20, _21, _22, _23, _24, _25, _26, _27, _28, _29, _30, _31, _32, _33, _34, _35, _36, _37, _38, _39, _40, _41, _42, _43, _44, _45, _46, _47, _48, _49, _50, _51, _52, _53, _54, _55, _56, _57, _58, _59, _60, _61, _62, _63, _64, _65, _66, _67, _68, _69, _70, _71, _72, _73, _74, _75, _76, _77, _78, _79, _80, _81, _82, _83, _84, _85, _86, _87, _88, _89, _90, _91, _92, _93, _94, _95, _96, _97, _98, _99, _100, _101, _102, _103, _104, _105, _106, _107, _108, _109, _110, _111, _112, _113, _114, _115, _116, _117, _118, _119, _120, _121, _122, _123, _124, _125, _126, _127, _128, _129, _130, _131, _132, _133, _134, _135, _136, _137, _138, _139, _140, _141, _142, _143, _144, _145, _146, _147, _148, _149, _150, _151, _152, _153, _154, _155, _156, _157, _158, _159, _160, _161, _162, _163, _164, _165, _166, _167, _168, _169, _170, _171, _172, _173, _174, _175, _176, _177, _178, _179, _180, _181, _182, _183, _184, _185, _186, _187, _188, _189, _190, _191, _192, _193, _194, _195, _196, _197, _198, _199, _200, N, ...) N
 
-#define RSEQ_N() 120, 119, 118, 117, 116, 115, 114, 113, 112, 111, 110, 109, 108, 107, 106, 105, 104, 103, 102, 101, 100, 99, 98, 97, 96, 95, 94, 93, 92, 91, 90, 89, 88, 87, 86, 85, 84, 83, 82, 81, 80, 79, 78, 77, 76, 75, 74, 73, 72, 71, 70, 69, 68, 67, 66, 65, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0
+#define RSEQ_N() 200, 199, 198, 197, 196, 195, 194, 193, 192, 191, 190, 189, 188, 187, 186, 185, 184, 183, 182, 181, 180, 179, 178, 177, 176, 175, 174, 173, 172, 171, 170, 169, 168, 167, 166, 165, 164, 163, 162, 161, 160, 159, 158, 157, 156, 155, 154, 153, 152, 151, 150, 149, 148, 147, 146, 145, 144, 143, 142, 141, 140, 139, 138, 137, 136, 135, 134, 133, 132, 131, 130, 129, 128, 127, 126, 125, 124, 123, 122, 121, 120, 119, 118, 117, 116, 115, 114, 113, 112, 111, 110, 109, 108, 107, 106, 105, 104, 103, 102, 101, 100, 99, 98, 97, 96, 95, 94, 93, 92, 91, 90, 89, 88, 87, 86, 85, 84, 83, 82, 81, 80, 79, 78, 77, 76, 75, 74, 73, 72, 71, 70, 69, 68, 67, 66, 65, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0
 
 #define COMPACT_FMT_2(fmt, value) fmt
 #define COMPACT_FMT_4(fmt, value, ...) fmt COMPACT_FMT_2(__VA_ARGS__)
@@ -108,6 +108,46 @@
 #define COMPACT_FMT_116(fmt, value, ...) fmt COMPACT_FMT_114(__VA_ARGS__)
 #define COMPACT_FMT_118(fmt, value, ...) fmt COMPACT_FMT_116(__VA_ARGS__)
 #define COMPACT_FMT_120(fmt, value, ...) fmt COMPACT_FMT_118(__VA_ARGS__)
+#define COMPACT_FMT_122(fmt, value, ...) fmt COMPACT_FMT_120(__VA_ARGS__)
+#define COMPACT_FMT_124(fmt, value, ...) fmt COMPACT_FMT_122(__VA_ARGS__)
+#define COMPACT_FMT_126(fmt, value, ...) fmt COMPACT_FMT_124(__VA_ARGS__)
+#define COMPACT_FMT_128(fmt, value, ...) fmt COMPACT_FMT_126(__VA_ARGS__)
+#define COMPACT_FMT_130(fmt, value, ...) fmt COMPACT_FMT_128(__VA_ARGS__)
+#define COMPACT_FMT_132(fmt, value, ...) fmt COMPACT_FMT_130(__VA_ARGS__)
+#define COMPACT_FMT_134(fmt, value, ...) fmt COMPACT_FMT_132(__VA_ARGS__)
+#define COMPACT_FMT_136(fmt, value, ...) fmt COMPACT_FMT_134(__VA_ARGS__)
+#define COMPACT_FMT_138(fmt, value, ...) fmt COMPACT_FMT_136(__VA_ARGS__)
+#define COMPACT_FMT_140(fmt, value, ...) fmt COMPACT_FMT_138(__VA_ARGS__)
+#define COMPACT_FMT_142(fmt, value, ...) fmt COMPACT_FMT_140(__VA_ARGS__)
+#define COMPACT_FMT_144(fmt, value, ...) fmt COMPACT_FMT_142(__VA_ARGS__)
+#define COMPACT_FMT_146(fmt, value, ...) fmt COMPACT_FMT_144(__VA_ARGS__)
+#define COMPACT_FMT_148(fmt, value, ...) fmt COMPACT_FMT_146(__VA_ARGS__)
+#define COMPACT_FMT_150(fmt, value, ...) fmt COMPACT_FMT_148(__VA_ARGS__)
+#define COMPACT_FMT_152(fmt, value, ...) fmt COMPACT_FMT_150(__VA_ARGS__)
+#define COMPACT_FMT_154(fmt, value, ...) fmt COMPACT_FMT_152(__VA_ARGS__)
+#define COMPACT_FMT_156(fmt, value, ...) fmt COMPACT_FMT_154(__VA_ARGS__)
+#define COMPACT_FMT_158(fmt, value, ...) fmt COMPACT_FMT_156(__VA_ARGS__)
+#define COMPACT_FMT_160(fmt, value, ...) fmt COMPACT_FMT_158(__VA_ARGS__)
+#define COMPACT_FMT_162(fmt, value, ...) fmt COMPACT_FMT_160(__VA_ARGS__)
+#define COMPACT_FMT_164(fmt, value, ...) fmt COMPACT_FMT_162(__VA_ARGS__)
+#define COMPACT_FMT_166(fmt, value, ...) fmt COMPACT_FMT_164(__VA_ARGS__)
+#define COMPACT_FMT_168(fmt, value, ...) fmt COMPACT_FMT_166(__VA_ARGS__)
+#define COMPACT_FMT_170(fmt, value, ...) fmt COMPACT_FMT_168(__VA_ARGS__)
+#define COMPACT_FMT_172(fmt, value, ...) fmt COMPACT_FMT_170(__VA_ARGS__)
+#define COMPACT_FMT_174(fmt, value, ...) fmt COMPACT_FMT_172(__VA_ARGS__)
+#define COMPACT_FMT_176(fmt, value, ...) fmt COMPACT_FMT_174(__VA_ARGS__)
+#define COMPACT_FMT_178(fmt, value, ...) fmt COMPACT_FMT_176(__VA_ARGS__)
+#define COMPACT_FMT_180(fmt, value, ...) fmt COMPACT_FMT_178(__VA_ARGS__)
+#define COMPACT_FMT_182(fmt, value, ...) fmt COMPACT_FMT_180(__VA_ARGS__)
+#define COMPACT_FMT_184(fmt, value, ...) fmt COMPACT_FMT_182(__VA_ARGS__)
+#define COMPACT_FMT_186(fmt, value, ...) fmt COMPACT_FMT_184(__VA_ARGS__)
+#define COMPACT_FMT_188(fmt, value, ...) fmt COMPACT_FMT_186(__VA_ARGS__)
+#define COMPACT_FMT_190(fmt, value, ...) fmt COMPACT_FMT_188(__VA_ARGS__)
+#define COMPACT_FMT_192(fmt, value, ...) fmt COMPACT_FMT_190(__VA_ARGS__)
+#define COMPACT_FMT_194(fmt, value, ...) fmt COMPACT_FMT_192(__VA_ARGS__)
+#define COMPACT_FMT_196(fmt, value, ...) fmt COMPACT_FMT_194(__VA_ARGS__)
+#define COMPACT_FMT_198(fmt, value, ...) fmt COMPACT_FMT_196(__VA_ARGS__)
+#define COMPACT_FMT_200(fmt, value, ...) fmt COMPACT_FMT_198(__VA_ARGS__)
 
 #define COMPACT_VALUES_2(fmt, value) value
 #define COMPACT_VALUES_4(fmt, value, ...) value, COMPACT_VALUES_2(__VA_ARGS__)
@@ -169,5 +209,45 @@
 #define COMPACT_VALUES_116(fmt, value, ...) value, COMPACT_VALUES_114(__VA_ARGS__)
 #define COMPACT_VALUES_118(fmt, value, ...) value, COMPACT_VALUES_116(__VA_ARGS__)
 #define COMPACT_VALUES_120(fmt, value, ...) value, COMPACT_VALUES_118(__VA_ARGS__)
+#define COMPACT_VALUES_122(fmt, value, ...) value, COMPACT_VALUES_120(__VA_ARGS__)
+#define COMPACT_VALUES_124(fmt, value, ...) value, COMPACT_VALUES_122(__VA_ARGS__)
+#define COMPACT_VALUES_126(fmt, value, ...) value, COMPACT_VALUES_124(__VA_ARGS__)
+#define COMPACT_VALUES_128(fmt, value, ...) value, COMPACT_VALUES_126(__VA_ARGS__)
+#define COMPACT_VALUES_130(fmt, value, ...) value, COMPACT_VALUES_128(__VA_ARGS__)
+#define COMPACT_VALUES_132(fmt, value, ...) value, COMPACT_VALUES_130(__VA_ARGS__)
+#define COMPACT_VALUES_134(fmt, value, ...) value, COMPACT_VALUES_132(__VA_ARGS__)
+#define COMPACT_VALUES_136(fmt, value, ...) value, COMPACT_VALUES_134(__VA_ARGS__)
+#define COMPACT_VALUES_138(fmt, value, ...) value, COMPACT_VALUES_136(__VA_ARGS__)
+#define COMPACT_VALUES_140(fmt, value, ...) value, COMPACT_VALUES_138(__VA_ARGS__)
+#define COMPACT_VALUES_142(fmt, value, ...) value, COMPACT_VALUES_140(__VA_ARGS__)
+#define COMPACT_VALUES_144(fmt, value, ...) value, COMPACT_VALUES_142(__VA_ARGS__)
+#define COMPACT_VALUES_146(fmt, value, ...) value, COMPACT_VALUES_144(__VA_ARGS__)
+#define COMPACT_VALUES_148(fmt, value, ...) value, COMPACT_VALUES_146(__VA_ARGS__)
+#define COMPACT_VALUES_150(fmt, value, ...) value, COMPACT_VALUES_148(__VA_ARGS__)
+#define COMPACT_VALUES_152(fmt, value, ...) value, COMPACT_VALUES_150(__VA_ARGS__)
+#define COMPACT_VALUES_154(fmt, value, ...) value, COMPACT_VALUES_152(__VA_ARGS__)
+#define COMPACT_VALUES_156(fmt, value, ...) value, COMPACT_VALUES_154(__VA_ARGS__)
+#define COMPACT_VALUES_158(fmt, value, ...) value, COMPACT_VALUES_156(__VA_ARGS__)
+#define COMPACT_VALUES_160(fmt, value, ...) value, COMPACT_VALUES_158(__VA_ARGS__)
+#define COMPACT_VALUES_162(fmt, value, ...) value, COMPACT_VALUES_160(__VA_ARGS__)
+#define COMPACT_VALUES_164(fmt, value, ...) value, COMPACT_VALUES_162(__VA_ARGS__)
+#define COMPACT_VALUES_166(fmt, value, ...) value, COMPACT_VALUES_164(__VA_ARGS__)
+#define COMPACT_VALUES_168(fmt, value, ...) value, COMPACT_VALUES_166(__VA_ARGS__)
+#define COMPACT_VALUES_170(fmt, value, ...) value, COMPACT_VALUES_168(__VA_ARGS__)
+#define COMPACT_VALUES_172(fmt, value, ...) value, COMPACT_VALUES_170(__VA_ARGS__)
+#define COMPACT_VALUES_174(fmt, value, ...) value, COMPACT_VALUES_172(__VA_ARGS__)
+#define COMPACT_VALUES_176(fmt, value, ...) value, COMPACT_VALUES_174(__VA_ARGS__)
+#define COMPACT_VALUES_178(fmt, value, ...) value, COMPACT_VALUES_176(__VA_ARGS__)
+#define COMPACT_VALUES_180(fmt, value, ...) value, COMPACT_VALUES_178(__VA_ARGS__)
+#define COMPACT_VALUES_182(fmt, value, ...) value, COMPACT_VALUES_180(__VA_ARGS__)
+#define COMPACT_VALUES_184(fmt, value, ...) value, COMPACT_VALUES_182(__VA_ARGS__)
+#define COMPACT_VALUES_186(fmt, value, ...) value, COMPACT_VALUES_184(__VA_ARGS__)
+#define COMPACT_VALUES_188(fmt, value, ...) value, COMPACT_VALUES_186(__VA_ARGS__)
+#define COMPACT_VALUES_190(fmt, value, ...) value, COMPACT_VALUES_188(__VA_ARGS__)
+#define COMPACT_VALUES_192(fmt, value, ...) value, COMPACT_VALUES_190(__VA_ARGS__)
+#define COMPACT_VALUES_194(fmt, value, ...) value, COMPACT_VALUES_192(__VA_ARGS__)
+#define COMPACT_VALUES_196(fmt, value, ...) value, COMPACT_VALUES_194(__VA_ARGS__)
+#define COMPACT_VALUES_198(fmt, value, ...) value, COMPACT_VALUES_196(__VA_ARGS__)
+#define COMPACT_VALUES_200(fmt, value, ...) value, COMPACT_VALUES_198(__VA_ARGS__)
 
 #endif

src/io_threads.c

@@ -1,3 +1,9 @@
+/*
+ * Copyright Valkey Contributors.
+ * All rights reserved.
+ * SPDX-License-Identifier: BSD 3-Clause
+ */
+
 #include "io_threads.h"
 
 static __thread int thread_id = 0; /* Thread local var */
@@ -303,6 +309,8 @@ void initIOThreads(void) {
 
     serverAssert(server.io_threads_num <= IO_THREADS_MAX_NUM);
 
+    prefetchCommandsBatchInit();
+
     /* Spawn and initialize the I/O threads. */
     for (int i = 1; i < server.io_threads_num; i++) {
         createIOThread(i);

src/kvstore.c

@@ -93,7 +93,7 @@ typedef struct {
 /**********************************/
 
 /* Get the dictionary pointer based on dict-index. */
-static dict *kvstoreGetDict(kvstore *kvs, int didx) {
+dict *kvstoreGetDict(kvstore *kvs, int didx) {
     return kvs->dicts[didx];
 }
 

src/kvstore.h

@@ -76,5 +76,6 @@ void kvstoreDictSetVal(kvstore *kvs, int didx, dictEntry *de, void *val);
 dictEntry *kvstoreDictTwoPhaseUnlinkFind(kvstore *kvs, int didx, const void *key, dictEntry ***plink, int *table_index);
 void kvstoreDictTwoPhaseUnlinkFree(kvstore *kvs, int didx, dictEntry *he, dictEntry **plink, int table_index);
 int kvstoreDictDelete(kvstore *kvs, int didx, const void *key);
+dict *kvstoreGetDict(kvstore *kvs, int didx);
 
 #endif /* DICTARRAY_H_ */