]> git.saurik.com Git - redis.git/blobdiff - src/redis.c
Correctly create shared.oomerr as an sds string.
[redis.git] / src / redis.c
index 17d7517f982cd0222d83ab6419dd72687ad4d82d..8cfabba7faa0e22963f2aaf761c9b1a27b230dce 100644 (file)
@@ -102,7 +102,10 @@ struct redisCommand *commandTable;
  * s: command not allowed in scripts.
  * R: random command. Command is not deterministic, that is, the same command
  *    with the same arguments, with the same key space, may have different
  * s: command not allowed in scripts.
  * R: random command. Command is not deterministic, that is, the same command
  *    with the same arguments, with the same key space, may have different
- *    results. For instance SPOP and RANDOMKEY are two random commands. */
+ *    results. For instance SPOP and RANDOMKEY are two random commands.
+ * S: Sort command output array if called from script, so that the output
+ *    is deterministic.
+ */
 struct redisCommand redisCommandTable[] = {
     {"get",getCommand,2,"r",0,NULL,1,1,1,0,0},
     {"set",setCommand,3,"wm",0,noPreloadGetKeys,1,1,1,0,0},
 struct redisCommand redisCommandTable[] = {
     {"get",getCommand,2,"r",0,NULL,1,1,1,0,0},
     {"set",setCommand,3,"wm",0,noPreloadGetKeys,1,1,1,0,0},
@@ -145,13 +148,13 @@ struct redisCommand redisCommandTable[] = {
     {"scard",scardCommand,2,"r",0,NULL,1,1,1,0,0},
     {"spop",spopCommand,2,"wRs",0,NULL,1,1,1,0,0},
     {"srandmember",srandmemberCommand,2,"rR",0,NULL,1,1,1,0,0},
     {"scard",scardCommand,2,"r",0,NULL,1,1,1,0,0},
     {"spop",spopCommand,2,"wRs",0,NULL,1,1,1,0,0},
     {"srandmember",srandmemberCommand,2,"rR",0,NULL,1,1,1,0,0},
-    {"sinter",sinterCommand,-2,"r",0,NULL,1,-1,1,0,0},
+    {"sinter",sinterCommand,-2,"rS",0,NULL,1,-1,1,0,0},
     {"sinterstore",sinterstoreCommand,-3,"wm",0,NULL,1,-1,1,0,0},
     {"sinterstore",sinterstoreCommand,-3,"wm",0,NULL,1,-1,1,0,0},
-    {"sunion",sunionCommand,-2,"r",0,NULL,1,-1,1,0,0},
+    {"sunion",sunionCommand,-2,"rS",0,NULL,1,-1,1,0,0},
     {"sunionstore",sunionstoreCommand,-3,"wm",0,NULL,1,-1,1,0,0},
     {"sunionstore",sunionstoreCommand,-3,"wm",0,NULL,1,-1,1,0,0},
-    {"sdiff",sdiffCommand,-2,"r",0,NULL,1,-1,1,0,0},
+    {"sdiff",sdiffCommand,-2,"rS",0,NULL,1,-1,1,0,0},
     {"sdiffstore",sdiffstoreCommand,-3,"wm",0,NULL,1,-1,1,0,0},
     {"sdiffstore",sdiffstoreCommand,-3,"wm",0,NULL,1,-1,1,0,0},
-    {"smembers",sinterCommand,2,"r",0,NULL,1,1,1,0,0},
+    {"smembers",sinterCommand,2,"rS",0,NULL,1,1,1,0,0},
     {"zadd",zaddCommand,-4,"wm",0,NULL,1,1,1,0,0},
     {"zincrby",zincrbyCommand,4,"wm",0,NULL,1,1,1,0,0},
     {"zrem",zremCommand,-3,"w",0,NULL,1,1,1,0,0},
     {"zadd",zaddCommand,-4,"wm",0,NULL,1,1,1,0,0},
     {"zincrby",zincrbyCommand,4,"wm",0,NULL,1,1,1,0,0},
     {"zrem",zremCommand,-3,"w",0,NULL,1,1,1,0,0},
@@ -177,8 +180,8 @@ struct redisCommand redisCommandTable[] = {
     {"hincrbyfloat",hincrbyfloatCommand,4,"wm",0,NULL,1,1,1,0,0},
     {"hdel",hdelCommand,-3,"w",0,NULL,1,1,1,0,0},
     {"hlen",hlenCommand,2,"r",0,NULL,1,1,1,0,0},
     {"hincrbyfloat",hincrbyfloatCommand,4,"wm",0,NULL,1,1,1,0,0},
     {"hdel",hdelCommand,-3,"w",0,NULL,1,1,1,0,0},
     {"hlen",hlenCommand,2,"r",0,NULL,1,1,1,0,0},
-    {"hkeys",hkeysCommand,2,"r",0,NULL,1,1,1,0,0},
-    {"hvals",hvalsCommand,2,"r",0,NULL,1,1,1,0,0},
+    {"hkeys",hkeysCommand,2,"rS",0,NULL,1,1,1,0,0},
+    {"hvals",hvalsCommand,2,"rS",0,NULL,1,1,1,0,0},
     {"hgetall",hgetallCommand,2,"r",0,NULL,1,1,1,0,0},
     {"hexists",hexistsCommand,3,"r",0,NULL,1,1,1,0,0},
     {"incrby",incrbyCommand,3,"wm",0,NULL,1,1,1,0,0},
     {"hgetall",hgetallCommand,2,"r",0,NULL,1,1,1,0,0},
     {"hexists",hexistsCommand,3,"r",0,NULL,1,1,1,0,0},
     {"incrby",incrbyCommand,3,"wm",0,NULL,1,1,1,0,0},
@@ -196,7 +199,7 @@ struct redisCommand redisCommandTable[] = {
     {"expireat",expireatCommand,3,"w",0,NULL,1,1,1,0,0},
     {"pexpire",pexpireCommand,3,"w",0,NULL,1,1,1,0,0},
     {"pexpireat",pexpireatCommand,3,"w",0,NULL,1,1,1,0,0},
     {"expireat",expireatCommand,3,"w",0,NULL,1,1,1,0,0},
     {"pexpire",pexpireCommand,3,"w",0,NULL,1,1,1,0,0},
     {"pexpireat",pexpireatCommand,3,"w",0,NULL,1,1,1,0,0},
-    {"keys",keysCommand,2,"r",0,NULL,0,0,0,0,0},
+    {"keys",keysCommand,2,"rS",0,NULL,0,0,0,0,0},
     {"dbsize",dbsizeCommand,1,"r",0,NULL,0,0,0,0,0},
     {"auth",authCommand,2,"rs",0,NULL,0,0,0,0,0},
     {"ping",pingCommand,1,"r",0,NULL,0,0,0,0,0},
     {"dbsize",dbsizeCommand,1,"r",0,NULL,0,0,0,0,0},
     {"auth",authCommand,2,"rs",0,NULL,0,0,0,0,0},
     {"ping",pingCommand,1,"r",0,NULL,0,0,0,0,0},
@@ -208,38 +211,37 @@ struct redisCommand redisCommandTable[] = {
     {"lastsave",lastsaveCommand,1,"r",0,NULL,0,0,0,0,0},
     {"type",typeCommand,2,"r",0,NULL,1,1,1,0,0},
     {"multi",multiCommand,1,"rs",0,NULL,0,0,0,0,0},
     {"lastsave",lastsaveCommand,1,"r",0,NULL,0,0,0,0,0},
     {"type",typeCommand,2,"r",0,NULL,1,1,1,0,0},
     {"multi",multiCommand,1,"rs",0,NULL,0,0,0,0,0},
-    {"exec",execCommand,1,"wms",0,NULL,0,0,0,0,0},
+    {"exec",execCommand,1,"s",0,NULL,0,0,0,0,0},
     {"discard",discardCommand,1,"rs",0,NULL,0,0,0,0,0},
     {"sync",syncCommand,1,"ars",0,NULL,0,0,0,0,0},
     {"flushdb",flushdbCommand,1,"w",0,NULL,0,0,0,0,0},
     {"flushall",flushallCommand,1,"w",0,NULL,0,0,0,0,0},
     {"discard",discardCommand,1,"rs",0,NULL,0,0,0,0,0},
     {"sync",syncCommand,1,"ars",0,NULL,0,0,0,0,0},
     {"flushdb",flushdbCommand,1,"w",0,NULL,0,0,0,0,0},
     {"flushall",flushallCommand,1,"w",0,NULL,0,0,0,0,0},
-    {"sort",sortCommand,-2,"wm",0,NULL,1,1,1,0,0},
+    {"sort",sortCommand,-2,"wmS",0,NULL,1,1,1,0,0},
     {"info",infoCommand,-1,"r",0,NULL,0,0,0,0,0},
     {"monitor",monitorCommand,1,"ars",0,NULL,0,0,0,0,0},
     {"ttl",ttlCommand,2,"r",0,NULL,1,1,1,0,0},
     {"pttl",pttlCommand,2,"r",0,NULL,1,1,1,0,0},
     {"persist",persistCommand,2,"w",0,NULL,1,1,1,0,0},
     {"slaveof",slaveofCommand,3,"aws",0,NULL,0,0,0,0,0},
     {"info",infoCommand,-1,"r",0,NULL,0,0,0,0,0},
     {"monitor",monitorCommand,1,"ars",0,NULL,0,0,0,0,0},
     {"ttl",ttlCommand,2,"r",0,NULL,1,1,1,0,0},
     {"pttl",pttlCommand,2,"r",0,NULL,1,1,1,0,0},
     {"persist",persistCommand,2,"w",0,NULL,1,1,1,0,0},
     {"slaveof",slaveofCommand,3,"aws",0,NULL,0,0,0,0,0},
-    {"debug",debugCommand,-2,"aws",0,NULL,0,0,0,0,0},
+    {"debug",debugCommand,-2,"as",0,NULL,0,0,0,0,0},
     {"config",configCommand,-2,"ar",0,NULL,0,0,0,0,0},
     {"subscribe",subscribeCommand,-2,"rps",0,NULL,0,0,0,0,0},
     {"unsubscribe",unsubscribeCommand,-1,"rps",0,NULL,0,0,0,0,0},
     {"psubscribe",psubscribeCommand,-2,"rps",0,NULL,0,0,0,0,0},
     {"punsubscribe",punsubscribeCommand,-1,"rps",0,NULL,0,0,0,0,0},
     {"config",configCommand,-2,"ar",0,NULL,0,0,0,0,0},
     {"subscribe",subscribeCommand,-2,"rps",0,NULL,0,0,0,0,0},
     {"unsubscribe",unsubscribeCommand,-1,"rps",0,NULL,0,0,0,0,0},
     {"psubscribe",psubscribeCommand,-2,"rps",0,NULL,0,0,0,0,0},
     {"punsubscribe",punsubscribeCommand,-1,"rps",0,NULL,0,0,0,0,0},
-    {"publish",publishCommand,3,"rpf",0,NULL,0,0,0,0,0},
+    {"publish",publishCommand,3,"pf",0,NULL,0,0,0,0,0},
     {"watch",watchCommand,-2,"rs",0,noPreloadGetKeys,1,-1,1,0,0},
     {"unwatch",unwatchCommand,1,"rs",0,NULL,0,0,0,0,0},
     {"watch",watchCommand,-2,"rs",0,noPreloadGetKeys,1,-1,1,0,0},
     {"unwatch",unwatchCommand,1,"rs",0,NULL,0,0,0,0,0},
-    {"cluster",clusterCommand,-2,"ar",0,NULL,0,0,0,0,0},
     {"restore",restoreCommand,4,"awm",0,NULL,1,1,1,0,0},
     {"migrate",migrateCommand,6,"aw",0,NULL,0,0,0,0,0},
     {"restore",restoreCommand,4,"awm",0,NULL,1,1,1,0,0},
     {"migrate",migrateCommand,6,"aw",0,NULL,0,0,0,0,0},
-    {"asking",askingCommand,1,"r",0,NULL,0,0,0,0,0},
     {"dump",dumpCommand,2,"ar",0,NULL,1,1,1,0,0},
     {"object",objectCommand,-2,"r",0,NULL,2,2,2,0,0},
     {"client",clientCommand,-2,"ar",0,NULL,0,0,0,0,0},
     {"dump",dumpCommand,2,"ar",0,NULL,1,1,1,0,0},
     {"object",objectCommand,-2,"r",0,NULL,2,2,2,0,0},
     {"client",clientCommand,-2,"ar",0,NULL,0,0,0,0,0},
-    {"eval",evalCommand,-3,"wms",0,zunionInterGetKeys,0,0,0,0,0},
-    {"evalsha",evalShaCommand,-3,"wms",0,zunionInterGetKeys,0,0,0,0,0},
+    {"eval",evalCommand,-3,"s",0,zunionInterGetKeys,0,0,0,0,0},
+    {"evalsha",evalShaCommand,-3,"s",0,zunionInterGetKeys,0,0,0,0,0},
     {"slowlog",slowlogCommand,-2,"r",0,NULL,0,0,0,0,0},
     {"slowlog",slowlogCommand,-2,"r",0,NULL,0,0,0,0,0},
-    {"script",scriptCommand,-2,"ras",0,NULL,0,0,0,0,0}
+    {"script",scriptCommand,-2,"ras",0,NULL,0,0,0,0,0},
+    {"time",timeCommand,1,"rR",0,NULL,0,0,0,0,0}
 };
 
 /*============================ Utility functions ============================ */
 };
 
 /*============================ Utility functions ============================ */
@@ -503,17 +505,6 @@ dictType keylistDictType = {
     dictListDestructor          /* val destructor */
 };
 
     dictListDestructor          /* val destructor */
 };
 
-/* Cluster nodes hash table, mapping nodes addresses 1.2.3.4:6379 to
- * clusterNode structures. */
-dictType clusterNodesDictType = {
-    dictSdsHash,                /* hash function */
-    NULL,                       /* key dup */
-    NULL,                       /* val dup */
-    dictSdsKeyCompare,          /* key compare */
-    dictSdsDestructor,          /* key destructor */
-    NULL                        /* val destructor */
-};
-
 int htNeedsResize(dict *dict) {
     long long size, used;
 
 int htNeedsResize(dict *dict) {
     long long size, used;
 
@@ -612,6 +603,110 @@ void updateLRUClock(void) {
                                                 REDIS_LRU_CLOCK_MAX;
 }
 
                                                 REDIS_LRU_CLOCK_MAX;
 }
 
+
+/* Add a sample to the operations per second array of samples. */
+void trackOperationsPerSecond(void) {
+    long long t = mstime() - server.ops_sec_last_sample_time;
+    long long ops = server.stat_numcommands - server.ops_sec_last_sample_ops;
+    long long ops_sec;
+
+    ops_sec = t > 0 ? (ops*1000/t) : 0;
+
+    server.ops_sec_samples[server.ops_sec_idx] = ops_sec;
+    server.ops_sec_idx = (server.ops_sec_idx+1) % REDIS_OPS_SEC_SAMPLES;
+    server.ops_sec_last_sample_time = mstime();
+    server.ops_sec_last_sample_ops = server.stat_numcommands;
+}
+
+/* Return the mean of all the samples. */
+long long getOperationsPerSecond(void) {
+    int j;
+    long long sum = 0;
+
+    for (j = 0; j < REDIS_OPS_SEC_SAMPLES; j++)
+        sum += server.ops_sec_samples[j];
+    return sum / REDIS_OPS_SEC_SAMPLES;
+}
+
+/* Check for timeouts. Returns non-zero if the client was terminated */
+int clientsCronHandleTimeout(redisClient *c) {
+    time_t now = server.unixtime;
+
+    if (server.maxidletime &&
+        !(c->flags & REDIS_SLAVE) &&    /* no timeout for slaves */
+        !(c->flags & REDIS_MASTER) &&   /* no timeout for masters */
+        !(c->flags & REDIS_BLOCKED) &&  /* no timeout for BLPOP */
+        dictSize(c->pubsub_channels) == 0 && /* no timeout for pubsub */
+        listLength(c->pubsub_patterns) == 0 &&
+        (now - c->lastinteraction > server.maxidletime))
+    {
+        redisLog(REDIS_VERBOSE,"Closing idle client");
+        freeClient(c);
+        return 1;
+    } else if (c->flags & REDIS_BLOCKED) {
+        if (c->bpop.timeout != 0 && c->bpop.timeout < now) {
+            addReply(c,shared.nullmultibulk);
+            unblockClientWaitingData(c);
+        }
+    }
+    return 0;
+}
+
+/* The client query buffer is an sds.c string that can end with a lot of
+ * free space not used, this function reclaims space if needed.
+ *
+ * The funciton always returns 0 as it never terminates the client. */
+int clientsCronResizeQueryBuffer(redisClient *c) {
+    size_t querybuf_size = sdsAllocSize(c->querybuf);
+    time_t idletime = server.unixtime - c->lastinteraction;
+
+    /* There are two conditions to resize the query buffer:
+     * 1) Query buffer is > BIG_ARG and too big for latest peak.
+     * 2) Client is inactive and the buffer is bigger than 1k. */
+    if (((querybuf_size > REDIS_MBULK_BIG_ARG) &&
+         (querybuf_size/(c->querybuf_peak+1)) > 2) ||
+         (querybuf_size > 1024 && idletime > 2))
+    {
+        /* Only resize the query buffer if it is actually wasting space. */
+        if (sdsavail(c->querybuf) > 1024) {
+            c->querybuf = sdsRemoveFreeSpace(c->querybuf);
+        }
+    }
+    /* Reset the peak again to capture the peak memory usage in the next
+     * cycle. */
+    c->querybuf_peak = 0;
+    return 0;
+}
+
+void clientsCron(void) {
+    /* Make sure to process at least 1/100 of clients per call.
+     * Since this function is called 10 times per second we are sure that
+     * in the worst case we process all the clients in 10 seconds.
+     * In normal conditions (a reasonable number of clients) we process
+     * all the clients in a shorter time. */
+    int numclients = listLength(server.clients);
+    int iterations = numclients/100;
+
+    if (iterations < 50)
+        iterations = (numclients < 50) ? numclients : 50;
+    while(listLength(server.clients) && iterations--) {
+        redisClient *c;
+        listNode *head;
+
+        /* Rotate the list, take the current head, process.
+         * This way if the client must be removed from the list it's the
+         * first element and we don't incur into O(N) computation. */
+        listRotate(server.clients);
+        head = listFirst(server.clients);
+        c = listNodeValue(head);
+        /* The following functions do different service checks on the client.
+         * The protocol is that they return non-zero if the client was
+         * terminated. */
+        if (clientsCronHandleTimeout(c)) continue;
+        if (clientsCronResizeQueryBuffer(c)) continue;
+    }
+}
+
 int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
     int j, loops = server.cronloops;
     REDIS_NOTUSED(eventLoop);
 int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
     int j, loops = server.cronloops;
     REDIS_NOTUSED(eventLoop);
@@ -624,6 +719,8 @@ int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
      * To access a global var is faster than calling time(NULL) */
     server.unixtime = time(NULL);
 
      * To access a global var is faster than calling time(NULL) */
     server.unixtime = time(NULL);
 
+    trackOperationsPerSecond();
+
     /* We have just 22 bits per object for LRU information.
      * So we use an (eventually wrapping) LRU clock with 10 seconds resolution.
      * 2^22 bits with 10 seconds resoluton is more or less 1.5 years.
     /* We have just 22 bits per object for LRU information.
      * So we use an (eventually wrapping) LRU clock with 10 seconds resolution.
      * 2^22 bits with 10 seconds resoluton is more or less 1.5 years.
@@ -681,9 +778,8 @@ int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
             zmalloc_used_memory());
     }
 
             zmalloc_used_memory());
     }
 
-    /* Close connections of timedout clients */
-    if ((server.maxidletime && !(loops % 100)) || server.bpop_blocked_clients)
-        closeTimedoutClients();
+    /* We need to do a few operations on clients asynchronously. */
+    clientsCron();
 
     /* Start a scheduled AOF rewrite if this was requested by the user while
      * a BGSAVE was in progress. */
 
     /* Start a scheduled AOF rewrite if this was requested by the user while
      * a BGSAVE was in progress. */
@@ -754,13 +850,13 @@ int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
      * in order to guarantee a strict consistency. */
     if (server.masterhost == NULL) activeExpireCycle();
 
      * in order to guarantee a strict consistency. */
     if (server.masterhost == NULL) activeExpireCycle();
 
+    /* Close clients that need to be closed asynchronous */
+    freeClientsInAsyncFreeQueue();
+
     /* Replication cron function -- used to reconnect to master and
      * to detect transfer failures. */
     if (!(loops % 10)) replicationCron();
 
     /* Replication cron function -- used to reconnect to master and
      * to detect transfer failures. */
     if (!(loops % 10)) replicationCron();
 
-    /* Run other sub-systems specific cron jobs */
-    if (server.cluster_enabled && !(loops % 10)) clusterCron();
-
     server.cronloops++;
     return 100;
 }
     server.cronloops++;
     return 100;
 }
@@ -826,6 +922,12 @@ void createSharedObjects(void) {
         "-LOADING Redis is loading the dataset in memory\r\n"));
     shared.slowscripterr = createObject(REDIS_STRING,sdsnew(
         "-BUSY Redis is busy running a script. You can only call SCRIPT KILL or SHUTDOWN NOSAVE.\r\n"));
         "-LOADING Redis is loading the dataset in memory\r\n"));
     shared.slowscripterr = createObject(REDIS_STRING,sdsnew(
         "-BUSY Redis is busy running a script. You can only call SCRIPT KILL or SHUTDOWN NOSAVE.\r\n"));
+    shared.bgsaveerr = createObject(REDIS_STRING,sdsnew(
+        "-MISCONF Redis is configured to save RDB snapshots, but is currently not able to persist on disk. Commands that may modify the data set are disabled. Please check Redis logs for details about the error.\r\n"));
+    shared.roslaveerr = createObject(REDIS_STRING,sdsnew(
+        "-READONLY You can't write against a read only slave.\r\n"));
+    shared.oomerr = createObject(REDIS_STRING,sdsnew(
+        "-OOM command not allowed when used memory > 'maxmemory'.\r\n"));
     shared.space = createObject(REDIS_STRING,sdsnew(" "));
     shared.colon = createObject(REDIS_STRING,sdsnew(":"));
     shared.plus = createObject(REDIS_STRING,sdsnew("+"));
     shared.space = createObject(REDIS_STRING,sdsnew(" "));
     shared.colon = createObject(REDIS_STRING,sdsnew(":"));
     shared.plus = createObject(REDIS_STRING,sdsnew("+"));
@@ -845,15 +947,25 @@ void createSharedObjects(void) {
     shared.unsubscribebulk = createStringObject("$11\r\nunsubscribe\r\n",18);
     shared.psubscribebulk = createStringObject("$10\r\npsubscribe\r\n",17);
     shared.punsubscribebulk = createStringObject("$12\r\npunsubscribe\r\n",19);
     shared.unsubscribebulk = createStringObject("$11\r\nunsubscribe\r\n",18);
     shared.psubscribebulk = createStringObject("$10\r\npsubscribe\r\n",17);
     shared.punsubscribebulk = createStringObject("$12\r\npunsubscribe\r\n",19);
-    shared.mbulk3 = createStringObject("*3\r\n",4);
-    shared.mbulk4 = createStringObject("*4\r\n",4);
+    shared.del = createStringObject("DEL",3);
+    shared.rpop = createStringObject("RPOP",4);
+    shared.lpop = createStringObject("LPOP",4);
     for (j = 0; j < REDIS_SHARED_INTEGERS; j++) {
         shared.integers[j] = createObject(REDIS_STRING,(void*)(long)j);
         shared.integers[j]->encoding = REDIS_ENCODING_INT;
     }
     for (j = 0; j < REDIS_SHARED_INTEGERS; j++) {
         shared.integers[j] = createObject(REDIS_STRING,(void*)(long)j);
         shared.integers[j]->encoding = REDIS_ENCODING_INT;
     }
+    for (j = 0; j < REDIS_SHARED_BULKHDR_LEN; j++) {
+        shared.mbulkhdr[j] = createObject(REDIS_STRING,
+            sdscatprintf(sdsempty(),"*%d\r\n",j));
+        shared.bulkhdr[j] = createObject(REDIS_STRING,
+            sdscatprintf(sdsempty(),"$%d\r\n",j));
+    }
 }
 
 void initServerConfig() {
 }
 
 void initServerConfig() {
+    getRandomHexChars(server.runid,REDIS_RUN_ID_SIZE);
+    server.runid[REDIS_RUN_ID_SIZE] = '\0';
+    server.arch_bits = (sizeof(long) == 8) ? 64 : 32;
     server.port = REDIS_SERVERPORT;
     server.bindaddr = NULL;
     server.unixsocket = NULL;
     server.port = REDIS_SERVERPORT;
     server.bindaddr = NULL;
     server.unixsocket = NULL;
@@ -893,8 +1005,8 @@ void initServerConfig() {
     server.maxmemory = 0;
     server.maxmemory_policy = REDIS_MAXMEMORY_VOLATILE_LRU;
     server.maxmemory_samples = 3;
     server.maxmemory = 0;
     server.maxmemory_policy = REDIS_MAXMEMORY_VOLATILE_LRU;
     server.maxmemory_samples = 3;
-    server.hash_max_zipmap_entries = REDIS_HASH_MAX_ZIPMAP_ENTRIES;
-    server.hash_max_zipmap_value = REDIS_HASH_MAX_ZIPMAP_VALUE;
+    server.hash_max_ziplist_entries = REDIS_HASH_MAX_ZIPLIST_ENTRIES;
+    server.hash_max_ziplist_value = REDIS_HASH_MAX_ZIPLIST_VALUE;
     server.list_max_ziplist_entries = REDIS_LIST_MAX_ZIPLIST_ENTRIES;
     server.list_max_ziplist_value = REDIS_LIST_MAX_ZIPLIST_VALUE;
     server.set_max_intset_entries = REDIS_SET_MAX_INTSET_ENTRIES;
     server.list_max_ziplist_entries = REDIS_LIST_MAX_ZIPLIST_ENTRIES;
     server.list_max_ziplist_value = REDIS_LIST_MAX_ZIPLIST_VALUE;
     server.set_max_intset_entries = REDIS_SET_MAX_INTSET_ENTRIES;
@@ -903,8 +1015,6 @@ void initServerConfig() {
     server.shutdown_asap = 0;
     server.repl_ping_slave_period = REDIS_REPL_PING_SLAVE_PERIOD;
     server.repl_timeout = REDIS_REPL_TIMEOUT;
     server.shutdown_asap = 0;
     server.repl_ping_slave_period = REDIS_REPL_PING_SLAVE_PERIOD;
     server.repl_timeout = REDIS_REPL_TIMEOUT;
-    server.cluster_enabled = 0;
-    server.cluster.configfile = zstrdup("nodes.conf");
     server.lua_caller = NULL;
     server.lua_time_limit = REDIS_LUA_TIME_LIMIT;
     server.lua_client = NULL;
     server.lua_caller = NULL;
     server.lua_time_limit = REDIS_LUA_TIME_LIMIT;
     server.lua_client = NULL;
@@ -924,8 +1034,20 @@ void initServerConfig() {
     server.repl_state = REDIS_REPL_NONE;
     server.repl_syncio_timeout = REDIS_REPL_SYNCIO_TIMEOUT;
     server.repl_serve_stale_data = 1;
     server.repl_state = REDIS_REPL_NONE;
     server.repl_syncio_timeout = REDIS_REPL_SYNCIO_TIMEOUT;
     server.repl_serve_stale_data = 1;
+    server.repl_slave_ro = 1;
     server.repl_down_since = -1;
 
     server.repl_down_since = -1;
 
+    /* Client output buffer limits */
+    server.client_obuf_limits[REDIS_CLIENT_LIMIT_CLASS_NORMAL].hard_limit_bytes = 0;
+    server.client_obuf_limits[REDIS_CLIENT_LIMIT_CLASS_NORMAL].soft_limit_bytes = 0;
+    server.client_obuf_limits[REDIS_CLIENT_LIMIT_CLASS_NORMAL].soft_limit_seconds = 0;
+    server.client_obuf_limits[REDIS_CLIENT_LIMIT_CLASS_SLAVE].hard_limit_bytes = 1024*1024*256;
+    server.client_obuf_limits[REDIS_CLIENT_LIMIT_CLASS_SLAVE].soft_limit_bytes = 1024*1024*64;
+    server.client_obuf_limits[REDIS_CLIENT_LIMIT_CLASS_SLAVE].soft_limit_seconds = 60;
+    server.client_obuf_limits[REDIS_CLIENT_LIMIT_CLASS_PUBSUB].hard_limit_bytes = 1024*1024*32;
+    server.client_obuf_limits[REDIS_CLIENT_LIMIT_CLASS_PUBSUB].soft_limit_bytes = 1024*1024*8;
+    server.client_obuf_limits[REDIS_CLIENT_LIMIT_CLASS_PUBSUB].soft_limit_seconds = 60;
+
     /* Double constants initialization */
     R_Zero = 0.0;
     R_PosInf = 1.0/R_Zero;
     /* Double constants initialization */
     R_Zero = 0.0;
     R_PosInf = 1.0/R_Zero;
@@ -939,6 +1061,7 @@ void initServerConfig() {
     populateCommandTable();
     server.delCommand = lookupCommandByCString("del");
     server.multiCommand = lookupCommandByCString("multi");
     populateCommandTable();
     server.delCommand = lookupCommandByCString("del");
     server.multiCommand = lookupCommandByCString("multi");
+    server.lpushCommand = lookupCommandByCString("lpush");
     
     /* Slow log */
     server.slowlog_log_slower_than = REDIS_SLOWLOG_LOG_SLOWER_THAN;
     
     /* Slow log */
     server.slowlog_log_slower_than = REDIS_SLOWLOG_LOG_SLOWER_THAN;
@@ -1002,6 +1125,7 @@ void initServer() {
 
     server.current_client = NULL;
     server.clients = listCreate();
 
     server.current_client = NULL;
     server.clients = listCreate();
+    server.clients_to_close = listCreate();
     server.slaves = listCreate();
     server.monitors = listCreate();
     server.unblocked_clients = listCreate();
     server.slaves = listCreate();
     server.monitors = listCreate();
     server.unblocked_clients = listCreate();
@@ -1059,7 +1183,13 @@ void initServer() {
     server.stat_peak_memory = 0;
     server.stat_fork_time = 0;
     server.stat_rejected_conn = 0;
     server.stat_peak_memory = 0;
     server.stat_fork_time = 0;
     server.stat_rejected_conn = 0;
+    memset(server.ops_sec_samples,0,sizeof(server.ops_sec_samples));
+    server.ops_sec_idx = 0;
+    server.ops_sec_last_sample_time = mstime();
+    server.ops_sec_last_sample_ops = 0;
     server.unixtime = time(NULL);
     server.unixtime = time(NULL);
+    server.lastbgsave_status = REDIS_OK;
+    server.stop_writes_on_bgsave_err = 1;
     aeCreateTimeEvent(server.el, 1, serverCron, NULL, NULL);
     if (server.ipfd > 0 && aeCreateFileEvent(server.el,server.ipfd,AE_READABLE,
         acceptTcpHandler,NULL) == AE_ERR) oom("creating file event");
     aeCreateTimeEvent(server.el, 1, serverCron, NULL, NULL);
     if (server.ipfd > 0 && aeCreateFileEvent(server.el,server.ipfd,AE_READABLE,
         acceptTcpHandler,NULL) == AE_ERR) oom("creating file event");
@@ -1076,7 +1206,16 @@ void initServer() {
         }
     }
 
         }
     }
 
-    if (server.cluster_enabled) clusterInit();
+    /* 32 bit instances are limited to 4GB of address space, so if there is
+     * no explicit limit in the user provided configuration we set a limit
+     * at 3.5GB using maxmemory with 'noeviction' policy'. This saves
+     * useless crashes of the Redis instance. */
+    if (server.arch_bits == 32 && server.maxmemory == 0) {
+        redisLog(REDIS_WARNING,"Warning: 32 bit instance detected but no memory limit set. Setting 3.5 GB maxmemory limit with 'noeviction' policy now.");
+        server.maxmemory = 3584LL*(1024*1024); /* 3584 MB = 3.5 GB */
+        server.maxmemory_policy = REDIS_MAXMEMORY_NO_EVICTION;
+    }
+
     scriptingInit();
     slowlogInit();
     bioInit();
     scriptingInit();
     slowlogInit();
     bioInit();
@@ -1103,6 +1242,7 @@ void populateCommandTable(void) {
             case 'f': c->flags |= REDIS_CMD_FORCE_REPLICATION; break;
             case 's': c->flags |= REDIS_CMD_NOSCRIPT; break;
             case 'R': c->flags |= REDIS_CMD_RANDOM; break;
             case 'f': c->flags |= REDIS_CMD_FORCE_REPLICATION; break;
             case 's': c->flags |= REDIS_CMD_NOSCRIPT; break;
             case 'R': c->flags |= REDIS_CMD_RANDOM; break;
+            case 'S': c->flags |= REDIS_CMD_SORT_FOR_SCRIPT; break;
             default: redisPanic("Unsupported command flag"); break;
             }
             f++;
             default: redisPanic("Unsupported command flag"); break;
             }
             f++;
@@ -1125,6 +1265,43 @@ void resetCommandTableStats(void) {
     }
 }
 
     }
 }
 
+/* ========================== Redis OP Array API ============================ */
+
+void redisOpArrayInit(redisOpArray *oa) {
+    oa->ops = NULL;
+    oa->numops = 0;
+}
+
+int redisOpArrayAppend(redisOpArray *oa, struct redisCommand *cmd, int dbid,
+                       robj **argv, int argc, int target)
+{
+    redisOp *op;
+
+    oa->ops = zrealloc(oa->ops,sizeof(redisOp)*(oa->numops+1));
+    op = oa->ops+oa->numops;
+    op->cmd = cmd;
+    op->dbid = dbid;
+    op->argv = argv;
+    op->argc = argc;
+    op->target = target;
+    oa->numops++;
+    return oa->numops;
+}
+
+void redisOpArrayFree(redisOpArray *oa) {
+    while(oa->numops) {
+        int j;
+        redisOp *op;
+
+        oa->numops--;
+        op = oa->ops+oa->numops;
+        for (j = 0; j < op->argc; j++)
+            decrRefCount(op->argv[j]);
+        zfree(op->argv);
+    }
+    zfree(oa->ops);
+}
+
 /* ====================== Commands lookup and execution ===================== */
 
 struct redisCommand *lookupCommand(sds name) {
 /* ====================== Commands lookup and execution ===================== */
 
 struct redisCommand *lookupCommand(sds name) {
@@ -1140,25 +1317,84 @@ struct redisCommand *lookupCommandByCString(char *s) {
     return cmd;
 }
 
     return cmd;
 }
 
+/* Propagate the specified command (in the context of the specified database id)
+ * to AOF, Slaves and Monitors.
+ *
+ * flags are an xor between:
+ * + REDIS_PROPAGATE_NONE (no propagation of command at all)
+ * + REDIS_PROPAGATE_AOF (propagate into the AOF file if is enabled)
+ * + REDIS_PROPAGATE_REPL (propagate into the replication link)
+ */
+void propagate(struct redisCommand *cmd, int dbid, robj **argv, int argc,
+               int flags)
+{
+    if (server.aof_state != REDIS_AOF_OFF && flags & REDIS_PROPAGATE_AOF)
+        feedAppendOnlyFile(cmd,dbid,argv,argc);
+    if (flags & REDIS_PROPAGATE_REPL && listLength(server.slaves))
+        replicationFeedSlaves(server.slaves,dbid,argv,argc);
+}
+
+/* Used inside commands to schedule the propagation of additional commands
+ * after the current command is propagated to AOF / Replication. */
+void alsoPropagate(struct redisCommand *cmd, int dbid, robj **argv, int argc,
+                   int target)
+{
+    redisOpArrayAppend(&server.also_propagate,cmd,dbid,argv,argc,target);
+}
+
 /* Call() is the core of Redis execution of a command */
 /* Call() is the core of Redis execution of a command */
-void call(redisClient *c) {
+void call(redisClient *c, int flags) {
     long long dirty, start = ustime(), duration;
 
     long long dirty, start = ustime(), duration;
 
+    /* Sent the command to clients in MONITOR mode, only if the commands are
+     * not geneated from reading an AOF. */
+    if (listLength(server.monitors) && !server.loading)
+        replicationFeedMonitors(c,server.monitors,c->db->id,c->argv,c->argc);
+
+    /* Call the command. */
+    redisOpArrayInit(&server.also_propagate);
     dirty = server.dirty;
     c->cmd->proc(c);
     dirty = server.dirty-dirty;
     duration = ustime()-start;
     dirty = server.dirty;
     c->cmd->proc(c);
     dirty = server.dirty-dirty;
     duration = ustime()-start;
-    c->cmd->microseconds += duration;
-    slowlogPushEntryIfNeeded(c->argv,c->argc,duration);
-    c->cmd->calls++;
-
-    if (server.aof_state != REDIS_AOF_OFF && dirty > 0)
-        feedAppendOnlyFile(c->cmd,c->db->id,c->argv,c->argc);
-    if ((dirty > 0 || c->cmd->flags & REDIS_CMD_FORCE_REPLICATION) &&
-        listLength(server.slaves))
-        replicationFeedSlaves(server.slaves,c->db->id,c->argv,c->argc);
-    if (listLength(server.monitors))
-        replicationFeedMonitors(server.monitors,c->db->id,c->argv,c->argc);
+
+    /* When EVAL is called loading the AOF we don't want commands called
+     * from Lua to go into the slowlog or to populate statistics. */
+    if (server.loading && c->flags & REDIS_LUA_CLIENT)
+        flags &= ~(REDIS_CALL_SLOWLOG | REDIS_CALL_STATS);
+
+    /* Log the command into the Slow log if needed, and populate the
+     * per-command statistics that we show in INFO commandstats. */
+    if (flags & REDIS_CALL_SLOWLOG)
+        slowlogPushEntryIfNeeded(c->argv,c->argc,duration);
+    if (flags & REDIS_CALL_STATS) {
+        c->cmd->microseconds += duration;
+        c->cmd->calls++;
+    }
+
+    /* Propagate the command into the AOF and replication link */
+    if (flags & REDIS_CALL_PROPAGATE) {
+        int flags = REDIS_PROPAGATE_NONE;
+
+        if (c->cmd->flags & REDIS_CMD_FORCE_REPLICATION)
+            flags |= REDIS_PROPAGATE_REPL;
+        if (dirty)
+            flags |= (REDIS_PROPAGATE_REPL | REDIS_PROPAGATE_AOF);
+        if (flags != REDIS_PROPAGATE_NONE)
+            propagate(c->cmd,c->db->id,c->argv,c->argc,flags);
+    }
+    /* Commands such as LPUSH or BRPOPLPUSH may propagate an additional
+     * PUSH command. */
+    if (server.also_propagate.numops) {
+        int j;
+        redisOp *rop;
+
+        for (j = 0; j < server.also_propagate.numops; j++) {
+            rop = &server.also_propagate.ops[j];
+            propagate(rop->cmd, rop->dbid, rop->argv, rop->argc, rop->target);
+        }
+        redisOpArrayFree(&server.also_propagate);
+    }
     server.stat_numcommands++;
 }
 
     server.stat_numcommands++;
 }
 
@@ -1202,39 +1438,36 @@ int processCommand(redisClient *c) {
         return REDIS_OK;
     }
 
         return REDIS_OK;
     }
 
-    /* If cluster is enabled, redirect here */
-    if (server.cluster_enabled &&
-                !(c->cmd->getkeys_proc == NULL && c->cmd->firstkey == 0)) {
-        int hashslot;
-
-        if (server.cluster.state != REDIS_CLUSTER_OK) {
-            addReplyError(c,"The cluster is down. Check with CLUSTER INFO for more information");
-            return REDIS_OK;
-        } else {
-            int ask;
-            clusterNode *n = getNodeByQuery(c,c->cmd,c->argv,c->argc,&hashslot,&ask);
-            if (n == NULL) {
-                addReplyError(c,"Multi keys request invalid in cluster");
-                return REDIS_OK;
-            } else if (n != server.cluster.myself) {
-                addReplySds(c,sdscatprintf(sdsempty(),
-                    "-%s %d %s:%d\r\n", ask ? "ASK" : "MOVED",
-                    hashslot,n->ip,n->port));
-                return REDIS_OK;
-            }
-        }
-    }
-
     /* Handle the maxmemory directive.
      *
      * First we try to free some memory if possible (if there are volatile
      * keys in the dataset). If there are not the only thing we can do
      * is returning an error. */
     /* Handle the maxmemory directive.
      *
      * First we try to free some memory if possible (if there are volatile
      * keys in the dataset). If there are not the only thing we can do
      * is returning an error. */
-    if (server.maxmemory) freeMemoryIfNeeded();
-    if (server.maxmemory && (c->cmd->flags & REDIS_CMD_DENYOOM) &&
-        zmalloc_used_memory() > server.maxmemory)
+    if (server.maxmemory) {
+        int retval = freeMemoryIfNeeded();
+        if ((c->cmd->flags & REDIS_CMD_DENYOOM) && retval == REDIS_ERR) {
+            addReply(c, shared.oomerr);
+            return REDIS_OK;
+        }
+    }
+
+    /* Don't accept write commands if there are problems persisting on disk. */
+    if (server.stop_writes_on_bgsave_err &&
+        server.saveparamslen > 0
+        && server.lastbgsave_status == REDIS_ERR &&
+        c->cmd->flags & REDIS_CMD_WRITE)
+    {
+        addReply(c, shared.bgsaveerr);
+        return REDIS_OK;
+    }
+
+    /* Don't accept wirte commands if this is a read only slave. But
+     * accept write commands if this is our master. */
+    if (server.masterhost && server.repl_slave_ro &&
+        !(c->flags & REDIS_MASTER) &&
+        c->cmd->flags & REDIS_CMD_WRITE)
     {
     {
-        addReplyError(c,"command not allowed when used memory > 'maxmemory'");
+        addReply(c, shared.roslaveerr);
         return REDIS_OK;
     }
 
         return REDIS_OK;
     }
 
@@ -1287,7 +1520,7 @@ int processCommand(redisClient *c) {
         queueMultiCommand(c);
         addReply(c,shared.queued);
     } else {
         queueMultiCommand(c);
         addReply(c,shared.queued);
     } else {
-        call(c);
+        call(c,REDIS_CALL_FULL);
     }
     return REDIS_OK;
 }
     }
     return REDIS_OK;
 }
@@ -1370,6 +1603,17 @@ void echoCommand(redisClient *c) {
     addReplyBulk(c,c->argv[1]);
 }
 
     addReplyBulk(c,c->argv[1]);
 }
 
+void timeCommand(redisClient *c) {
+    struct timeval tv;
+
+    /* gettimeofday() can only fail if &tv is a bad addresss so we
+     * don't check for errors. */
+    gettimeofday(&tv,NULL);
+    addReplyMultiBulkLen(c,2);
+    addReplyBulkLongLong(c,tv.tv_sec);
+    addReplyBulkLongLong(c,tv.tv_usec);
+}
+
 /* Convert an amount of bytes into a human readable string in the form
  * of 100B, 2G, 100M, 4K, and so forth. */
 void bytesToHuman(char *s, unsigned long long n) {
 /* Convert an amount of bytes into a human readable string in the form
  * of 100B, 2G, 100M, 4K, and so forth. */
 void bytesToHuman(char *s, unsigned long long n) {
@@ -1420,10 +1664,11 @@ sds genRedisInfoString(char *section) {
             "redis_version:%s\r\n"
             "redis_git_sha1:%s\r\n"
             "redis_git_dirty:%d\r\n"
             "redis_version:%s\r\n"
             "redis_git_sha1:%s\r\n"
             "redis_git_dirty:%d\r\n"
-            "arch_bits:%s\r\n"
+            "arch_bits:%d\r\n"
             "multiplexing_api:%s\r\n"
             "gcc_version:%d.%d.%d\r\n"
             "process_id:%ld\r\n"
             "multiplexing_api:%s\r\n"
             "gcc_version:%d.%d.%d\r\n"
             "process_id:%ld\r\n"
+            "run_id:%s\r\n"
             "tcp_port:%d\r\n"
             "uptime_in_seconds:%ld\r\n"
             "uptime_in_days:%ld\r\n"
             "tcp_port:%d\r\n"
             "uptime_in_seconds:%ld\r\n"
             "uptime_in_days:%ld\r\n"
@@ -1431,7 +1676,7 @@ sds genRedisInfoString(char *section) {
             REDIS_VERSION,
             redisGitSHA1(),
             strtol(redisGitDirty(),NULL,10) > 0,
             REDIS_VERSION,
             redisGitSHA1(),
             strtol(redisGitDirty(),NULL,10) > 0,
-            (sizeof(long) == 8) ? "64" : "32",
+            server.arch_bits,
             aeGetApiName(),
 #ifdef __GNUC__
             __GNUC__,__GNUC_MINOR__,__GNUC_PATCHLEVEL__,
             aeGetApiName(),
 #ifdef __GNUC__
             __GNUC__,__GNUC_MINOR__,__GNUC_PATCHLEVEL__,
@@ -1439,6 +1684,7 @@ sds genRedisInfoString(char *section) {
             0,0,0,
 #endif
             (long) getpid(),
             0,0,0,
 #endif
             (long) getpid(),
+            server.runid,
             server.port,
             uptime,
             uptime/(3600*24),
             server.port,
             uptime,
             uptime/(3600*24),
@@ -1450,7 +1696,7 @@ sds genRedisInfoString(char *section) {
         if (sections++) info = sdscat(info,"\r\n");
         info = sdscatprintf(info,
             "# Clients\r\n"
         if (sections++) info = sdscat(info,"\r\n");
         info = sdscatprintf(info,
             "# Clients\r\n"
-            "connected_clients:%d\r\n"
+            "connected_clients:%lu\r\n"
             "client_longest_output_list:%lu\r\n"
             "client_biggest_input_buf:%lu\r\n"
             "blocked_clients:%d\r\n",
             "client_longest_output_list:%lu\r\n"
             "client_biggest_input_buf:%lu\r\n"
             "blocked_clients:%d\r\n",
@@ -1498,12 +1744,14 @@ sds genRedisInfoString(char *section) {
             "changes_since_last_save:%lld\r\n"
             "bgsave_in_progress:%d\r\n"
             "last_save_time:%ld\r\n"
             "changes_since_last_save:%lld\r\n"
             "bgsave_in_progress:%d\r\n"
             "last_save_time:%ld\r\n"
+            "last_bgsave_status:%s\r\n"
             "bgrewriteaof_in_progress:%d\r\n",
             server.loading,
             server.aof_state != REDIS_AOF_OFF,
             server.dirty,
             server.rdb_child_pid != -1,
             server.lastsave,
             "bgrewriteaof_in_progress:%d\r\n",
             server.loading,
             server.aof_state != REDIS_AOF_OFF,
             server.dirty,
             server.rdb_child_pid != -1,
             server.lastsave,
+            server.lastbgsave_status == REDIS_OK ? "ok" : "err",
             server.aof_child_pid != -1);
 
         if (server.aof_state != REDIS_AOF_OFF) {
             server.aof_child_pid != -1);
 
         if (server.aof_state != REDIS_AOF_OFF) {
@@ -1559,16 +1807,18 @@ sds genRedisInfoString(char *section) {
             "# Stats\r\n"
             "total_connections_received:%lld\r\n"
             "total_commands_processed:%lld\r\n"
             "# Stats\r\n"
             "total_connections_received:%lld\r\n"
             "total_commands_processed:%lld\r\n"
+            "instantaneous_ops_per_sec:%lld\r\n"
             "rejected_connections:%lld\r\n"
             "expired_keys:%lld\r\n"
             "evicted_keys:%lld\r\n"
             "keyspace_hits:%lld\r\n"
             "keyspace_misses:%lld\r\n"
             "pubsub_channels:%ld\r\n"
             "rejected_connections:%lld\r\n"
             "expired_keys:%lld\r\n"
             "evicted_keys:%lld\r\n"
             "keyspace_hits:%lld\r\n"
             "keyspace_misses:%lld\r\n"
             "pubsub_channels:%ld\r\n"
-            "pubsub_patterns:%u\r\n"
+            "pubsub_patterns:%lu\r\n"
             "latest_fork_usec:%lld\r\n",
             server.stat_numconnections,
             server.stat_numcommands,
             "latest_fork_usec:%lld\r\n",
             server.stat_numconnections,
             server.stat_numcommands,
+            getOperationsPerSecond(),
             server.stat_rejected_conn,
             server.stat_expiredkeys,
             server.stat_evictedkeys,
             server.stat_rejected_conn,
             server.stat_expiredkeys,
             server.stat_evictedkeys,
@@ -1618,7 +1868,7 @@ sds genRedisInfoString(char *section) {
             }
         }
         info = sdscatprintf(info,
             }
         }
         info = sdscatprintf(info,
-            "connected_slaves:%d\r\n",
+            "connected_slaves:%lu\r\n",
             listLength(server.slaves));
         if (listLength(server.slaves)) {
             int slaveid = 0;
             listLength(server.slaves));
         if (listLength(server.slaves)) {
             int slaveid = 0;
@@ -1684,15 +1934,6 @@ sds genRedisInfoString(char *section) {
         }
     }
 
         }
     }
 
-    /* Clusetr */
-    if (allsections || defsections || !strcasecmp(section,"cluster")) {
-        if (sections++) info = sdscat(info,"\r\n");
-        info = sdscatprintf(info,
-        "# Cluster\r\n"
-        "cluster_enabled:%d\r\n",
-        server.cluster_enabled);
-    }
-
     /* Key space */
     if (allsections || defsections || !strcasecmp(section,"keyspace")) {
         if (sections++) info = sdscat(info,"\r\n");
     /* Key space */
     if (allsections || defsections || !strcasecmp(section,"keyspace")) {
         if (sections++) info = sdscat(info,"\r\n");
@@ -1738,23 +1979,57 @@ void monitorCommand(redisClient *c) {
 /* ============================ Maxmemory directive  ======================== */
 
 /* This function gets called when 'maxmemory' is set on the config file to limit
 /* ============================ Maxmemory directive  ======================== */
 
 /* This function gets called when 'maxmemory' is set on the config file to limit
- * the max memory used by the server, and we are out of memory.
- * This function will try to, in order:
+ * the max memory used by the server, before processing a command.
+ *
+ * The goal of the function is to free enough memory to keep Redis under the
+ * configured memory limit.
  *
  *
- * - Free objects from the free list
- * - Try to remove keys with an EXPIRE set
+ * The function starts calculating how many bytes should be freed to keep
+ * Redis under the limit, and enters a loop selecting the best keys to
+ * evict accordingly to the configured policy.
  *
  *
- * It is not possible to free enough memory to reach used-memory < maxmemory
- * the server will start refusing commands that will enlarge even more the
- * memory usage.
+ * If all the bytes needed to return back under the limit were freed the
+ * function returns REDIS_OK, otherwise REDIS_ERR is returned, and the caller
+ * should block the execution of commands that will result in more memory
+ * used by the server.
  */
  */
-void freeMemoryIfNeeded(void) {
-    /* Remove keys accordingly to the active policy as long as we are
-     * over the memory limit. */
-    if (server.maxmemory_policy == REDIS_MAXMEMORY_NO_EVICTION) return;
+int freeMemoryIfNeeded(void) {
+    size_t mem_used, mem_tofree, mem_freed;
+    int slaves = listLength(server.slaves);
+
+    /* Remove the size of slaves output buffers and AOF buffer from the
+     * count of used memory. */
+    mem_used = zmalloc_used_memory();
+    if (slaves) {
+        listIter li;
+        listNode *ln;
+
+        listRewind(server.slaves,&li);
+        while((ln = listNext(&li))) {
+            redisClient *slave = listNodeValue(ln);
+            unsigned long obuf_bytes = getClientOutputBufferMemoryUsage(slave);
+            if (obuf_bytes > mem_used)
+                mem_used = 0;
+            else
+                mem_used -= obuf_bytes;
+        }
+    }
+    if (server.aof_state != REDIS_AOF_OFF) {
+        mem_used -= sdslen(server.aof_buf);
+        mem_used -= sdslen(server.aof_rewrite_buf);
+    }
+
+    /* Check if we are over the memory limit. */
+    if (mem_used <= server.maxmemory) return REDIS_OK;
 
 
-    while (server.maxmemory && zmalloc_used_memory() > server.maxmemory) {
-        int j, k, freed = 0;
+    if (server.maxmemory_policy == REDIS_MAXMEMORY_NO_EVICTION)
+        return REDIS_ERR; /* We need to free memory, but policy forbids. */
+
+    /* Compute how much memory we need to free. */
+    mem_tofree = mem_used - server.maxmemory;
+    mem_freed = 0;
+    while (mem_freed < mem_tofree) {
+        int j, k, keys_freed = 0;
 
         for (j = 0; j < server.dbnum; j++) {
             long bestval = 0; /* just to prevent warning */
 
         for (j = 0; j < server.dbnum; j++) {
             long bestval = 0; /* just to prevent warning */
@@ -1827,16 +2102,36 @@ void freeMemoryIfNeeded(void) {
 
             /* Finally remove the selected key. */
             if (bestkey) {
 
             /* Finally remove the selected key. */
             if (bestkey) {
+                long long delta;
+
                 robj *keyobj = createStringObject(bestkey,sdslen(bestkey));
                 propagateExpire(db,keyobj);
                 robj *keyobj = createStringObject(bestkey,sdslen(bestkey));
                 propagateExpire(db,keyobj);
+                /* We compute the amount of memory freed by dbDelete() alone.
+                 * It is possible that actually the memory needed to propagate
+                 * the DEL in AOF and replication link is greater than the one
+                 * we are freeing removing the key, but we can't account for
+                 * that otherwise we would never exit the loop.
+                 *
+                 * AOF and Output buffer memory will be freed eventually so
+                 * we only care about memory used by the key space. */
+                delta = (long long) zmalloc_used_memory();
                 dbDelete(db,keyobj);
                 dbDelete(db,keyobj);
+                delta -= (long long) zmalloc_used_memory();
+                mem_freed += delta;
                 server.stat_evictedkeys++;
                 decrRefCount(keyobj);
                 server.stat_evictedkeys++;
                 decrRefCount(keyobj);
-                freed++;
+                keys_freed++;
+
+                /* When the memory to free starts to be big enough, we may
+                 * start spending so much time here that is impossible to
+                 * deliver data to the slaves fast enough, so we force the
+                 * transmission here inside the loop. */
+                if (slaves) flushSlavesOutputBuffers();
             }
         }
             }
         }
-        if (!freed) return; /* nothing to free... */
+        if (!keys_freed) return REDIS_ERR; /* nothing to free... */
     }
     }
+    return REDIS_OK;
 }
 
 /* =================================== Main! ================================ */
 }
 
 /* =================================== Main! ================================ */
@@ -1899,7 +2194,8 @@ void usage() {
     fprintf(stderr,"Usage: ./redis-server [/path/to/redis.conf] [options]\n");
     fprintf(stderr,"       ./redis-server - (read config from stdin)\n");
     fprintf(stderr,"       ./redis-server -v or --version\n");
     fprintf(stderr,"Usage: ./redis-server [/path/to/redis.conf] [options]\n");
     fprintf(stderr,"       ./redis-server - (read config from stdin)\n");
     fprintf(stderr,"       ./redis-server -v or --version\n");
-    fprintf(stderr,"       ./redis-server -h or --help\n\n");
+    fprintf(stderr,"       ./redis-server -h or --help\n");
+    fprintf(stderr,"       ./redis-server --test-memory <megabytes>\n\n");
     fprintf(stderr,"Examples:\n");
     fprintf(stderr,"       ./redis-server (run the server with default conf)\n");
     fprintf(stderr,"       ./redis-server /etc/redis/6379.conf\n");
     fprintf(stderr,"Examples:\n");
     fprintf(stderr,"       ./redis-server (run the server with default conf)\n");
     fprintf(stderr,"       ./redis-server /etc/redis/6379.conf\n");
@@ -1918,7 +2214,7 @@ void redisAsciiArt(void) {
         redisGitSHA1(),
         strtol(redisGitDirty(),NULL,10) > 0,
         (sizeof(long) == 8) ? "64" : "32",
         redisGitSHA1(),
         strtol(redisGitDirty(),NULL,10) > 0,
         (sizeof(long) == 8) ? "64" : "32",
-        server.cluster_enabled ? "cluster" : "stand alone",
+        "stand alone",
         server.port,
         (long) getpid()
     );
         server.port,
         (long) getpid()
     );
@@ -1955,6 +2251,8 @@ void setupSignalHandlers(void) {
     return;
 }
 
     return;
 }
 
+void memtest(size_t megabytes, int passes);
+
 int main(int argc, char **argv) {
     long long start;
     struct timeval tv;
 int main(int argc, char **argv) {
     long long start;
     struct timeval tv;
@@ -1976,6 +2274,17 @@ int main(int argc, char **argv) {
             strcmp(argv[1], "--version") == 0) version();
         if (strcmp(argv[1], "--help") == 0 ||
             strcmp(argv[1], "-h") == 0) usage();
             strcmp(argv[1], "--version") == 0) version();
         if (strcmp(argv[1], "--help") == 0 ||
             strcmp(argv[1], "-h") == 0) usage();
+        if (strcmp(argv[1], "--test-memory") == 0) {
+            if (argc == 3) {
+                memtest(atoi(argv[2]),50);
+                exit(0);
+            } else {
+                fprintf(stderr,"Please specify the amount of memory to test in megabytes.\n");
+                fprintf(stderr,"Example: ./redis-server --test-memory 4096\n\n");
+                exit(1);
+            }
+        }
+
         /* First argument is the config file name? */
         if (argv[j][0] != '-' || argv[j][1] != '-')
             configfile = argv[j++];
         /* First argument is the config file name? */
         if (argv[j][0] != '-' || argv[j][1] != '-')
             configfile = argv[j++];