Now maxmemory, VM, and everything else uses the fast RSS memory used estimation instead of raw memory reported by zmalloc(). This means that setting maxmemory to 2GB will really have the effect of using up to 2GB of memory.

src/aof.c

@@ -280,11 +280,11 @@ int loadAppendOnlyFile(char *filename) {
 
         /* Handle swapping while loading big datasets when VM is on */
         force_swapout = 0;
-        if ((zmalloc_used_memory() - server.vm_max_memory) > 1024*1024*32)
+        if ((redisEstimateRSS() - server.vm_max_memory) > 1024*1024*32)
             force_swapout = 1;
 
         if (server.vm_enabled && force_swapout) {
-            while (zmalloc_used_memory() > server.vm_max_memory) {
+            while (redisEstimateRSS() > server.vm_max_memory) {
                 if (vmSwapOneObjectBlocking() == REDIS_ERR) break;
             }
         }

src/rdb.c

@@ -885,16 +885,16 @@ int rdbLoad(char *filename) {
 
         /* Flush data on disk once 32 MB of additional RAM are used... */
         force_swapout = 0;
-        if ((zmalloc_used_memory() - server.vm_max_memory) > 1024*1024*32)
+        if ((redisEstimateRSS() - server.vm_max_memory) > 1024*1024*32)
             force_swapout = 1;
 
         /* If we have still some hope of having some value fitting memory
          * then we try random sampling. */
         if (!swap_all_values && server.vm_enabled && force_swapout) {
-            while (zmalloc_used_memory() > server.vm_max_memory) {
+            while (redisEstimateRSS() > server.vm_max_memory) {
                 if (vmSwapOneObjectBlocking() == REDIS_ERR) break;
             }
-            if (zmalloc_used_memory() > server.vm_max_memory)
+            if (redisEstimateRSS() > server.vm_max_memory)
                 swap_all_values = 1; /* We are already using too much mem */
         }
     }

src/redis.c

@@ -545,7 +545,7 @@ int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
         redisLog(REDIS_VERBOSE,"%d clients connected (%d slaves), %zu bytes in use",
             listLength(server.clients)-listLength(server.slaves),
             listLength(server.slaves),
-            zmalloc_used_memory());
+            redisEstimateRSS());
     }
 
     /* Close connections of timedout clients */
@@ -590,9 +590,7 @@ int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
     /* Swap a few keys on disk if we are over the memory limit and VM
      * is enbled. Try to free objects from the free list first. */
     if (vmCanSwapOut()) {
-        while (server.vm_enabled && zmalloc_used_memory() >
-                server.vm_max_memory)
-        {
+        while (server.vm_enabled && redisEstimateRSS() > server.vm_max_memory) {
             int retval;
 
             if (tryFreeOneObjectFromFreelist() == REDIS_OK) continue;
@@ -600,7 +598,7 @@ int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
                         vmSwapOneObjectBlocking() :
                         vmSwapOneObjectThreaded();
             if (retval == REDIS_ERR && !(loops % 300) &&
-                zmalloc_used_memory() >
+                redisEstimateRSS() >
                 (server.vm_max_memory+server.vm_max_memory/10))
             {
                 redisLog(REDIS_WARNING,"WARNING: vm-max-memory limit exceeded by more than 10%% but unable to swap more objects out!");
@@ -940,7 +938,7 @@ int processCommand(redisClient *c) {
      * is returning an error. */
     if (server.maxmemory) freeMemoryIfNeeded();
     if (server.maxmemory && (cmd->flags & REDIS_CMD_DENYOOM) &&
-        zmalloc_used_memory() > server.maxmemory)
+        redisEstimateRSS() > server.maxmemory)
     {
         addReplyError(c,"command not allowed when used memory > 'maxmemory'");
         return REDIS_OK;
@@ -1059,7 +1057,7 @@ sds genRedisInfoString(void) {
     getrusage(RUSAGE_SELF, &self_ru);
     getrusage(RUSAGE_CHILDREN, &c_ru);
 
-    bytesToHuman(hmem,zmalloc_used_memory());
+    bytesToHuman(hmem,redisEstimateRSS());
     info = sdscatprintf(sdsempty(),
         "redis_version:%s\r\n"
         "redis_git_sha1:%s\r\n"
@@ -1079,8 +1077,8 @@ sds genRedisInfoString(void) {
         "blocked_clients:%d\r\n"
         "used_memory:%zu\r\n"
         "used_memory_human:%s\r\n"
-        "used_memory_rss:%zu\r\n"
-        "used_memory_estimated_rss:%zu\r\n"
+        "used_memory_zmalloc:%zu\r\n"
+        "used_memory_raw_rss:%zu\r\n"
         "mem_fragmentation_ratio:%.2f\r\n"
         "use_tcmalloc:%d\r\n"
         "changes_since_last_save:%lld\r\n"
@@ -1114,10 +1112,10 @@ sds genRedisInfoString(void) {
         listLength(server.clients)-listLength(server.slaves),
         listLength(server.slaves),
         server.blpop_blocked_clients,
-        zmalloc_used_memory(),
-        hmem,
-        zmalloc_get_rss(),
         redisEstimateRSS(),
+        hmem,
+        zmalloc_used_memory(),
+        zmalloc_get_rss(),
         zmalloc_get_fragmentation_ratio(),
 #ifdef USE_TCMALLOC
         1,
@@ -1285,7 +1283,7 @@ size_t redisEstimateRSS(void) {
 void freeMemoryIfNeeded(void) {
     /* Remove keys accordingly to the active policy as long as we are
      * over the memory limit. */
-    while (server.maxmemory && zmalloc_used_memory() > server.maxmemory) {
+    while (server.maxmemory && redisEstimateRSS() > server.maxmemory) {
         int j, k, freed = 0;
 
         /* Basic strategy -- remove objects from the free list. */