negative caching implemented

[redis.git] / src / redis.c

diff --git a/src/redis.c b/src/redis.c
index a3f04f1126e3b0ca83802c921579f30b415e0a18..65cf3ace9c045b1fbcffa6347aba51f37dc87626 100644 (file)
--- a/src/redis.c
+++ b/src/redis.c
@@ -74,10 +74,14 @@ struct redisCommand readonlyCommandTable[] = {
     {"setnx",setnxCommand,3,REDIS_CMD_DENYOOM,NULL,0,0,0},
     {"setex",setexCommand,4,REDIS_CMD_DENYOOM,NULL,0,0,0},
     {"append",appendCommand,3,REDIS_CMD_DENYOOM,NULL,1,1,1},
     {"setnx",setnxCommand,3,REDIS_CMD_DENYOOM,NULL,0,0,0},
     {"setex",setexCommand,4,REDIS_CMD_DENYOOM,NULL,0,0,0},
     {"append",appendCommand,3,REDIS_CMD_DENYOOM,NULL,1,1,1},

-    {"substr",substrCommand,4,0,NULL,1,1,1},

     {"strlen",strlenCommand,2,0,NULL,1,1,1},
     {"del",delCommand,-2,0,NULL,0,0,0},
     {"exists",existsCommand,2,0,NULL,1,1,1},
     {"strlen",strlenCommand,2,0,NULL,1,1,1},
     {"del",delCommand,-2,0,NULL,0,0,0},
     {"exists",existsCommand,2,0,NULL,1,1,1},

+    {"setbit",setbitCommand,4,REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"getbit",getbitCommand,3,0,NULL,1,1,1},
+    {"setrange",setrangeCommand,4,REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"getrange",getrangeCommand,4,0,NULL,1,1,1},
+    {"substr",getrangeCommand,4,0,NULL,1,1,1},

     {"incr",incrCommand,2,REDIS_CMD_DENYOOM,NULL,1,1,1},
     {"decr",decrCommand,2,REDIS_CMD_DENYOOM,NULL,1,1,1},
     {"mget",mgetCommand,-2,0,NULL,1,-1,1},
     {"incr",incrCommand,2,REDIS_CMD_DENYOOM,NULL,1,1,1},
     {"decr",decrCommand,2,REDIS_CMD_DENYOOM,NULL,1,1,1},
     {"mget",mgetCommand,-2,0,NULL,1,-1,1},


@@ -89,6 +93,7 @@ struct redisCommand readonlyCommandTable[] = {
     {"rpop",rpopCommand,2,0,NULL,1,1,1},
     {"lpop",lpopCommand,2,0,NULL,1,1,1},
     {"brpop",brpopCommand,-3,0,NULL,1,1,1},
     {"rpop",rpopCommand,2,0,NULL,1,1,1},
     {"lpop",lpopCommand,2,0,NULL,1,1,1},
     {"brpop",brpopCommand,-3,0,NULL,1,1,1},

+    {"brpoplpush",brpoplpushCommand,4,REDIS_CMD_DENYOOM,NULL,1,2,1},

     {"blpop",blpopCommand,-3,0,NULL,1,1,1},
     {"llen",llenCommand,2,0,NULL,1,1,1},
     {"lindex",lindexCommand,3,0,NULL,1,1,1},
     {"blpop",blpopCommand,-3,0,NULL,1,1,1},
     {"llen",llenCommand,2,0,NULL,1,1,1},
     {"lindex",lindexCommand,3,0,NULL,1,1,1},


@@ -96,7 +101,7 @@ struct redisCommand readonlyCommandTable[] = {
     {"lrange",lrangeCommand,4,0,NULL,1,1,1},
     {"ltrim",ltrimCommand,4,0,NULL,1,1,1},
     {"lrem",lremCommand,4,0,NULL,1,1,1},
     {"lrange",lrangeCommand,4,0,NULL,1,1,1},
     {"ltrim",ltrimCommand,4,0,NULL,1,1,1},
     {"lrem",lremCommand,4,0,NULL,1,1,1},

-    {"rpoplpush",rpoplpushcommand,3,REDIS_CMD_DENYOOM,NULL,1,2,1},
+    {"rpoplpush",rpoplpushCommand,3,REDIS_CMD_DENYOOM,NULL,1,2,1},

     {"sadd",saddCommand,3,REDIS_CMD_DENYOOM,NULL,1,1,1},
     {"srem",sremCommand,3,0,NULL,1,1,1},
     {"smove",smoveCommand,4,0,NULL,1,2,1},
     {"sadd",saddCommand,3,REDIS_CMD_DENYOOM,NULL,1,1,1},
     {"srem",sremCommand,3,0,NULL,1,1,1},
     {"smove",smoveCommand,4,0,NULL,1,2,1},


@@ -120,10 +125,11 @@ struct redisCommand readonlyCommandTable[] = {
     {"zinterstore",zinterstoreCommand,-4,REDIS_CMD_DENYOOM,zunionInterBlockClientOnSwappedKeys,0,0,0},
     {"zrange",zrangeCommand,-4,0,NULL,1,1,1},
     {"zrangebyscore",zrangebyscoreCommand,-4,0,NULL,1,1,1},
     {"zinterstore",zinterstoreCommand,-4,REDIS_CMD_DENYOOM,zunionInterBlockClientOnSwappedKeys,0,0,0},
     {"zrange",zrangeCommand,-4,0,NULL,1,1,1},
     {"zrangebyscore",zrangebyscoreCommand,-4,0,NULL,1,1,1},

+    {"zrevrangebyscore",zrevrangebyscoreCommand,-4,0,NULL,1,1,1},

     {"zcount",zcountCommand,4,0,NULL,1,1,1},
     {"zrevrange",zrevrangeCommand,-4,0,NULL,1,1,1},
     {"zcard",zcardCommand,2,0,NULL,1,1,1},
     {"zcount",zcountCommand,4,0,NULL,1,1,1},
     {"zrevrange",zrevrangeCommand,-4,0,NULL,1,1,1},
     {"zcard",zcardCommand,2,0,NULL,1,1,1},

-    {"zscore",zscoreCommand,3,REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"zscore",zscoreCommand,3,0,NULL,1,1,1},

     {"zrank",zrankCommand,3,0,NULL,1,1,1},
     {"zrevrank",zrevrankCommand,3,0,NULL,1,1,1},
     {"hset",hsetCommand,4,REDIS_CMD_DENYOOM,NULL,1,1,1},
     {"zrank",zrankCommand,3,0,NULL,1,1,1},
     {"zrevrank",zrevrankCommand,3,0,NULL,1,1,1},
     {"hset",hsetCommand,4,REDIS_CMD_DENYOOM,NULL,1,1,1},


@@ -187,11 +193,13 @@ struct redisCommand readonlyCommandTable[] = {
 /*============================ Utility functions ============================ */
 
 void redisLog(int level, const char *fmt, ...) {
 /*============================ Utility functions ============================ */
 
 void redisLog(int level, const char *fmt, ...) {

+    const int syslogLevelMap[] = { LOG_DEBUG, LOG_INFO, LOG_NOTICE, LOG_WARNING };
+    const char *c = ".-*#";
+    time_t now = time(NULL);

     va_list ap;
     FILE *fp;
     va_list ap;
     FILE *fp;

-    char *c = ".-*#";

     char buf[64];
     char buf[64];

-    time_t now;
+    char msg[REDIS_MAX_LOGMSG_LEN];

 
     if (level < server.verbosity) return;
 
 
     if (level < server.verbosity) return;
 


@@ -199,15 +207,16 @@ void redisLog(int level, const char *fmt, ...) {
     if (!fp) return;
 
     va_start(ap, fmt);
     if (!fp) return;
 
     va_start(ap, fmt);

-    now = time(NULL);
-    strftime(buf,64,"%d %b %H:%M:%S",localtime(&now));
-    fprintf(fp,"[%d] %s %c ",(int)getpid(),buf,c[level]);
-    vfprintf(fp, fmt, ap);
-    fprintf(fp,"\n");
-    fflush(fp);
+    vsnprintf(msg, sizeof(msg), fmt, ap);

     va_end(ap);
 
     va_end(ap);
 

+    strftime(buf,sizeof(buf),"%d %b %H:%M:%S",localtime(&now));
+    fprintf(fp,"[%d] %s %c %s\n",(int)getpid(),buf,c[level],msg);
+    fflush(fp);
+

     if (server.logfile) fclose(fp);
     if (server.logfile) fclose(fp);

+
+    if (server.syslog_enabled) syslog(syslogLevelMap[level], "%s", msg);

 }
 
 /* Redis generally does not try to recover from out of memory conditions
 }
 
 /* Redis generally does not try to recover from out of memory conditions


@@ -251,6 +260,15 @@ int dictSdsKeyCompare(void *privdata, const void *key1,
     return memcmp(key1, key2, l1) == 0;
 }
 
     return memcmp(key1, key2, l1) == 0;
 }
 

+/* A case insensitive version used for the command lookup table. */
+int dictSdsKeyCaseCompare(void *privdata, const void *key1,
+        const void *key2)
+{
+    DICT_NOTUSED(privdata);
+
+    return strcasecmp(key1, key2) == 0;
+}
+

 void dictRedisObjectDestructor(void *privdata, void *val)
 {
     DICT_NOTUSED(privdata);
 void dictRedisObjectDestructor(void *privdata, void *val)
 {
     DICT_NOTUSED(privdata);


@@ -282,6 +300,10 @@ unsigned int dictSdsHash(const void *key) {
     return dictGenHashFunction((unsigned char*)key, sdslen((char*)key));
 }
 
     return dictGenHashFunction((unsigned char*)key, sdslen((char*)key));
 }
 

+unsigned int dictSdsCaseHash(const void *key) {
+    return dictGenCaseHashFunction((unsigned char*)key, sdslen((char*)key));
+}
+

 int dictEncObjKeyCompare(void *privdata, const void *key1,
         const void *key2)
 {
 int dictEncObjKeyCompare(void *privdata, const void *key1,
         const void *key2)
 {


@@ -323,7 +345,7 @@ unsigned int dictEncObjHash(const void *key) {
     }
 }
 
     }
 }
 

-/* Sets type */
+/* Sets type and diskstore negative caching hash table */

 dictType setDictType = {
     dictEncObjHash,            /* hash function */
     NULL,                      /* key dup */
 dictType setDictType = {
     dictEncObjHash,            /* hash function */
     NULL,                      /* key dup */


@@ -363,6 +385,16 @@ dictType keyptrDictType = {
     NULL                       /* val destructor */
 };
 
     NULL                       /* val destructor */
 };
 

+/* Command table. sds string -> command struct pointer. */
+dictType commandTableDictType = {
+    dictSdsCaseHash,           /* hash function */
+    NULL,                      /* key dup */
+    NULL,                      /* val dup */
+    dictSdsKeyCaseCompare,     /* key compare */
+    dictSdsDestructor,         /* key destructor */
+    NULL                       /* val destructor */
+};
+

 /* Hash type hash table (note that small hashes are represented with zimpaps) */
 dictType hashDictType = {
     dictEncObjHash,             /* hash function */
 /* Hash type hash table (note that small hashes are represented with zimpaps) */
 dictType hashDictType = {
     dictEncObjHash,             /* hash function */


@@ -478,6 +510,10 @@ void activeExpireCycle(void) {
     }
 }
 
     }
 }
 

+void updateLRUClock(void) {
+    server.lruclock = (time(NULL)/REDIS_LRU_CLOCK_RESOLUTION) &
+                                                REDIS_LRU_CLOCK_MAX;
+}

 
 int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
     int j, loops = server.cronloops++;
 
 int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
     int j, loops = server.cronloops++;


@@ -490,19 +526,19 @@ int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
      * in objects at every object access, and accuracy is not needed.
      * To access a global var is faster than calling time(NULL) */
     server.unixtime = time(NULL);
      * in objects at every object access, and accuracy is not needed.
      * To access a global var is faster than calling time(NULL) */
     server.unixtime = time(NULL);

-    /* We have just 21 bits per object for LRU information.
-     * So we use an (eventually wrapping) LRU clock with minutes resolution.
+    /* 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.

      *
      *

-     * When we need to select what object to swap, we compute the minimum
-     * time distance between the current lruclock and the object last access
-     * lruclock info. Even if clocks will wrap on overflow, there is
-     * the interesting property that we are sure that at least
-     * ABS(A-B) minutes passed between current time and timestamp B.
+     * Note that even if this will wrap after 1.5 years it's not a problem,
+     * everything will still work but just some object will appear younger
+     * to Redis. But for this to happen a given object should never be touched
+     * for 1.5 years.

      *
      *

-     * This is not precise but we don't need at all precision, but just
-     * something statistically reasonable.
+     * Note that you can change the resolution altering the
+     * REDIS_LRU_CLOCK_RESOLUTION define.

      */
      */

-    server.lruclock = (time(NULL)/60)&((1<<21)-1);
+    updateLRUClock();

 
     /* We received a SIGTERM, shutting down here in a safe way, as it is
      * not ok doing so inside the signal handler. */
 
     /* We received a SIGTERM, shutting down here in a safe way, as it is
      * not ok doing so inside the signal handler. */


@@ -544,7 +580,7 @@ int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
     }
 
     /* Close connections of timedout clients */
     }
 
     /* Close connections of timedout clients */

-    if ((server.maxidletime && !(loops % 100)) || server.blpop_blocked_clients)
+    if ((server.maxidletime && !(loops % 100)) || server.bpop_blocked_clients)

         closeTimedoutClients();
 
     /* Check if a background saving or AOF rewrite in progress terminated */
         closeTimedoutClients();
 
     /* Check if a background saving or AOF rewrite in progress terminated */


@@ -560,7 +596,7 @@ int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
             }
             updateDictResizePolicy();
         }
             }
             updateDictResizePolicy();
         }

-    } else {
+    } else if (!server.ds_enabled) {

         /* If there is not a background saving in progress check if
          * we have to save now */
          time_t now = time(NULL);
         /* If there is not a background saving in progress check if
          * we have to save now */
          time_t now = time(NULL);


@@ -582,40 +618,14 @@ 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();
 

-    /* 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)
-        {
-            int retval;
-
-            if (tryFreeOneObjectFromFreelist() == REDIS_OK) continue;
-            retval = (server.vm_max_threads == 0) ?
-                        vmSwapOneObjectBlocking() :
-                        vmSwapOneObjectThreaded();
-            if (retval == REDIS_ERR && !(loops % 300) &&
-                zmalloc_used_memory() >
-                (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!");
-            }
-            /* Note that when using threade I/O we free just one object,
-             * because anyway when the I/O thread in charge to swap this
-             * object out will finish, the handler of completed jobs
-             * will try to swap more objects if we are still out of memory. */
-            if (retval == REDIS_ERR || server.vm_max_threads > 0) break;
-        }
-    }
+    /* Remove a few cached objects from memory if we are over the
+     * configured memory limit */
+    if (server.ds_enabled) cacheCron();
+
+    /* Replication cron function -- used to reconnect to master and
+     * to detect transfer failures. */
+    if (!(loops % 10)) replicationCron();

 
 

-    /* Check if we should connect to a MASTER */
-    if (server.replstate == REDIS_REPL_CONNECT && !(loops % 10)) {
-        redisLog(REDIS_NOTICE,"Connecting to MASTER...");
-        if (syncWithMaster() == REDIS_OK) {
-            redisLog(REDIS_NOTICE,"MASTER <-> SLAVE sync succeeded");
-            if (server.appendonly) rewriteAppendOnlyFileBackground();
-        }
-    }

     return 100;
 }
 
     return 100;
 }
 


@@ -624,21 +634,22 @@ int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
  * for ready file descriptors. */
 void beforeSleep(struct aeEventLoop *eventLoop) {
     REDIS_NOTUSED(eventLoop);
  * for ready file descriptors. */
 void beforeSleep(struct aeEventLoop *eventLoop) {
     REDIS_NOTUSED(eventLoop);

+    listNode *ln;
+    redisClient *c;

 
 

-    /* Awake clients that got all the swapped keys they requested */
-    if (server.vm_enabled && listLength(server.io_ready_clients)) {
+    /* Awake clients that got all the on disk keys they requested */
+    if (server.ds_enabled && listLength(server.io_ready_clients)) {

         listIter li;
         listIter li;

-        listNode *ln;

 
         listRewind(server.io_ready_clients,&li);
         while((ln = listNext(&li))) {
 
         listRewind(server.io_ready_clients,&li);
         while((ln = listNext(&li))) {

-            redisClient *c = ln->value;
+            c = ln->value;

             struct redisCommand *cmd;
 
             /* Resume the client. */
             listDelNode(server.io_ready_clients,ln);
             c->flags &= (~REDIS_IO_WAIT);
             struct redisCommand *cmd;
 
             /* Resume the client. */
             listDelNode(server.io_ready_clients,ln);
             c->flags &= (~REDIS_IO_WAIT);

-            server.vm_blocked_clients--;
+            server.cache_blocked_clients--;

             aeCreateFileEvent(server.el, c->fd, AE_READABLE,
                 readQueryFromClient, c);
             cmd = lookupCommand(c->argv[0]->ptr);
             aeCreateFileEvent(server.el, c->fd, AE_READABLE,
                 readQueryFromClient, c);
             cmd = lookupCommand(c->argv[0]->ptr);


@@ -650,6 +661,19 @@ void beforeSleep(struct aeEventLoop *eventLoop) {
                 processInputBuffer(c);
         }
     }
                 processInputBuffer(c);
         }
     }

+
+    /* Try to process pending commands for clients that were just unblocked. */
+    while (listLength(server.unblocked_clients)) {
+        ln = listFirst(server.unblocked_clients);
+        redisAssert(ln != NULL);
+        c = ln->value;
+        listDelNode(server.unblocked_clients,ln);
+
+        /* Process remaining data in the input buffer. */
+        if (c->querybuf && sdslen(c->querybuf) > 0)
+            processInputBuffer(c);
+    }
+

     /* Write the AOF buffer on disk */
     flushAppendOnlyFile();
 }
     /* Write the AOF buffer on disk */
     flushAppendOnlyFile();
 }


@@ -681,6 +705,8 @@ void createSharedObjects(void) {
         "-ERR source and destination objects are the same\r\n"));
     shared.outofrangeerr = createObject(REDIS_STRING,sdsnew(
         "-ERR index out of range\r\n"));
         "-ERR source and destination objects are the same\r\n"));
     shared.outofrangeerr = createObject(REDIS_STRING,sdsnew(
         "-ERR index out of range\r\n"));

+    shared.loadingerr = createObject(REDIS_STRING,sdsnew(
+        "-LOADING Redis is loading the dataset in memory\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("+"));


@@ -709,13 +735,20 @@ void createSharedObjects(void) {
 }
 
 void initServerConfig() {
 }
 
 void initServerConfig() {

-    server.dbnum = REDIS_DEFAULT_DBNUM;

     server.port = REDIS_SERVERPORT;
     server.port = REDIS_SERVERPORT;

+    server.bindaddr = NULL;
+    server.unixsocket = NULL;
+    server.ipfd = -1;
+    server.sofd = -1;
+    server.dbnum = REDIS_DEFAULT_DBNUM;

     server.verbosity = REDIS_VERBOSE;
     server.maxidletime = REDIS_MAXIDLETIME;
     server.saveparams = NULL;
     server.verbosity = REDIS_VERBOSE;
     server.maxidletime = REDIS_MAXIDLETIME;
     server.saveparams = NULL;

+    server.loading = 0;

     server.logfile = NULL; /* NULL = log on standard output */
     server.logfile = NULL; /* NULL = log on standard output */

-    server.bindaddr = NULL;
+    server.syslog_enabled = 0;
+    server.syslog_ident = zstrdup("redis");
+    server.syslog_facility = LOG_LOCAL0;

     server.glueoutputbuf = 1;
     server.daemonize = 0;
     server.appendonly = 0;
     server.glueoutputbuf = 1;
     server.daemonize = 0;
     server.appendonly = 0;


@@ -731,15 +764,14 @@ void initServerConfig() {
     server.rdbcompression = 1;
     server.activerehashing = 1;
     server.maxclients = 0;
     server.rdbcompression = 1;
     server.activerehashing = 1;
     server.maxclients = 0;

-    server.blpop_blocked_clients = 0;
+    server.bpop_blocked_clients = 0;

     server.maxmemory = 0;
     server.maxmemory = 0;

-    server.vm_enabled = 0;
-    server.vm_swap_file = zstrdup("/tmp/redis-%p.vm");
-    server.vm_page_size = 256;          /* 256 bytes per page */
-    server.vm_pages = 1024*1024*100;    /* 104 millions of pages */
-    server.vm_max_memory = 1024LL*1024*1024*1; /* 1 GB of RAM */
-    server.vm_max_threads = 4;
-    server.vm_blocked_clients = 0;
+    server.maxmemory_policy = REDIS_MAXMEMORY_VOLATILE_LRU;
+    server.maxmemory_samples = 3;
+    server.ds_enabled = 0;
+    server.ds_path = sdsnew("/tmp/redis.ds");
+    server.cache_max_memory = 64LL*1024*1024; /* 64 MB of RAM */
+    server.cache_blocked_clients = 0;

     server.hash_max_zipmap_entries = REDIS_HASH_MAX_ZIPMAP_ENTRIES;
     server.hash_max_zipmap_value = REDIS_HASH_MAX_ZIPMAP_VALUE;
     server.list_max_ziplist_entries = REDIS_LIST_MAX_ZIPLIST_ENTRIES;
     server.hash_max_zipmap_entries = REDIS_HASH_MAX_ZIPMAP_ENTRIES;
     server.hash_max_zipmap_value = REDIS_HASH_MAX_ZIPMAP_VALUE;
     server.list_max_ziplist_entries = REDIS_LIST_MAX_ZIPLIST_ENTRIES;


@@ -747,6 +779,7 @@ void initServerConfig() {
     server.set_max_intset_entries = REDIS_SET_MAX_INTSET_ENTRIES;
     server.shutdown_asap = 0;
 
     server.set_max_intset_entries = REDIS_SET_MAX_INTSET_ENTRIES;
     server.shutdown_asap = 0;
 

+    updateLRUClock();

     resetServerSaveParams();
 
     appendServerSaveParams(60*60,1);  /* save after 1 hour and 1 change */
     resetServerSaveParams();
 
     appendServerSaveParams(60*60,1);  /* save after 1 hour and 1 change */


@@ -759,12 +792,21 @@ void initServerConfig() {
     server.masterport = 6379;
     server.master = NULL;
     server.replstate = REDIS_REPL_NONE;
     server.masterport = 6379;
     server.master = NULL;
     server.replstate = REDIS_REPL_NONE;

+    server.repl_serve_stale_data = 1;

 
     /* Double constants initialization */
     R_Zero = 0.0;
     R_PosInf = 1.0/R_Zero;
     R_NegInf = -1.0/R_Zero;
     R_Nan = R_Zero/R_Zero;
 
     /* Double constants initialization */
     R_Zero = 0.0;
     R_PosInf = 1.0/R_Zero;
     R_NegInf = -1.0/R_Zero;
     R_Nan = R_Zero/R_Zero;

+
+    /* Command table -- we intiialize it here as it is part of the
+     * initial configuration, since command names may be changed via
+     * redis.conf using the rename-command directive. */
+    server.commands = dictCreate(&commandTableDictType,NULL);
+    populateCommandTable();
+    server.delCommand = lookupCommandByCString("del");
+    server.multiCommand = lookupCommandByCString("multi");

 }
 
 void initServer() {
 }
 
 void initServer() {


@@ -774,22 +816,37 @@ void initServer() {
     signal(SIGPIPE, SIG_IGN);
     setupSigSegvAction();
 
     signal(SIGPIPE, SIG_IGN);
     setupSigSegvAction();
 

-    server.mainthread = pthread_self();
-    server.devnull = fopen("/dev/null","w");
-    if (server.devnull == NULL) {
-        redisLog(REDIS_WARNING, "Can't open /dev/null: %s", server.neterr);
-        exit(1);
+    if (server.syslog_enabled) {
+        openlog(server.syslog_ident, LOG_PID | LOG_NDELAY | LOG_NOWAIT,
+            server.syslog_facility);

     }
     }

+
+    server.mainthread = pthread_self();

     server.clients = listCreate();
     server.slaves = listCreate();
     server.monitors = listCreate();
     server.clients = listCreate();
     server.slaves = listCreate();
     server.monitors = listCreate();

-    server.objfreelist = listCreate();
+    server.unblocked_clients = listCreate();
+    server.cache_flush_queue = listCreate();
+    server.cache_flush_delay = 0;
+

     createSharedObjects();
     server.el = aeCreateEventLoop();
     server.db = zmalloc(sizeof(redisDb)*server.dbnum);
     createSharedObjects();
     server.el = aeCreateEventLoop();
     server.db = zmalloc(sizeof(redisDb)*server.dbnum);

-    server.fd = anetTcpServer(server.neterr, server.port, server.bindaddr);
-    if (server.fd == -1) {
-        redisLog(REDIS_WARNING, "Opening TCP port: %s", server.neterr);
+    server.ipfd = anetTcpServer(server.neterr,server.port,server.bindaddr);
+    if (server.ipfd == ANET_ERR) {
+        redisLog(REDIS_WARNING, "Opening port: %s", server.neterr);
+        exit(1);
+    }
+    if (server.unixsocket != NULL) {
+        unlink(server.unixsocket); /* don't care if this fails */
+        server.sofd = anetUnixServer(server.neterr,server.unixsocket);
+        if (server.sofd == ANET_ERR) {
+            redisLog(REDIS_WARNING, "Opening socket: %s", server.neterr);
+            exit(1);
+        }
+    }
+    if (server.ipfd < 0 && server.sofd < 0) {
+        redisLog(REDIS_WARNING, "Configured to not listen anywhere, exiting.");

         exit(1);
     }
     for (j = 0; j < server.dbnum; j++) {
         exit(1);
     }
     for (j = 0; j < server.dbnum; j++) {


@@ -797,8 +854,10 @@ void initServer() {
         server.db[j].expires = dictCreate(&keyptrDictType,NULL);
         server.db[j].blocking_keys = dictCreate(&keylistDictType,NULL);
         server.db[j].watched_keys = dictCreate(&keylistDictType,NULL);
         server.db[j].expires = dictCreate(&keyptrDictType,NULL);
         server.db[j].blocking_keys = dictCreate(&keylistDictType,NULL);
         server.db[j].watched_keys = dictCreate(&keylistDictType,NULL);

-        if (server.vm_enabled)
+        if (server.ds_enabled) {

             server.db[j].io_keys = dictCreate(&keylistDictType,NULL);
             server.db[j].io_keys = dictCreate(&keylistDictType,NULL);

+            server.db[j].io_negcache = dictCreate(&setDictType,NULL);
+        }

         server.db[j].id = j;
     }
     server.pubsub_channels = dictCreate(&keylistDictType,NULL);
         server.db[j].id = j;
     }
     server.pubsub_channels = dictCreate(&keylistDictType,NULL);


@@ -815,11 +874,16 @@ void initServer() {
     server.stat_numcommands = 0;
     server.stat_numconnections = 0;
     server.stat_expiredkeys = 0;
     server.stat_numcommands = 0;
     server.stat_numconnections = 0;
     server.stat_expiredkeys = 0;

+    server.stat_evictedkeys = 0;

     server.stat_starttime = time(NULL);
     server.stat_starttime = time(NULL);

+    server.stat_keyspace_misses = 0;
+    server.stat_keyspace_hits = 0;

     server.unixtime = time(NULL);
     aeCreateTimeEvent(server.el, 1, serverCron, NULL, NULL);
     server.unixtime = time(NULL);
     aeCreateTimeEvent(server.el, 1, serverCron, NULL, NULL);

-    if (aeCreateFileEvent(server.el, server.fd, AE_READABLE,
-        acceptHandler, NULL) == AE_ERR) oom("creating file event");
+    if (server.ipfd > 0 && aeCreateFileEvent(server.el,server.ipfd,AE_READABLE,
+        acceptTcpHandler,NULL) == AE_ERR) oom("creating file event");
+    if (server.sofd > 0 && aeCreateFileEvent(server.el,server.sofd,AE_READABLE,
+        acceptUnixHandler,NULL) == AE_ERR) oom("creating file event");

 
     if (server.appendonly) {
         server.appendfd = open(server.appendfilename,O_WRONLY|O_APPEND|O_CREAT,0644);
 
     if (server.appendonly) {
         server.appendfd = open(server.appendfilename,O_WRONLY|O_APPEND|O_CREAT,0644);


@@ -830,34 +894,37 @@ void initServer() {
         }
     }
 
         }
     }
 

-    if (server.vm_enabled) vmInit();
+    if (server.ds_enabled) dsInit();

 }
 
 }
 

-int qsortRedisCommands(const void *r1, const void *r2) {
-    return strcasecmp(
-        ((struct redisCommand*)r1)->name,
-        ((struct redisCommand*)r2)->name);
-}
+/* Populates the Redis Command Table starting from the hard coded list
+ * we have on top of redis.c file. */
+void populateCommandTable(void) {
+    int j;
+    int numcommands = sizeof(readonlyCommandTable)/sizeof(struct redisCommand);
+
+    for (j = 0; j < numcommands; j++) {
+        struct redisCommand *c = readonlyCommandTable+j;
+        int retval;

 
 

-void sortCommandTable() {
-    /* Copy and sort the read-only version of the command table */
-    commandTable = (struct redisCommand*)zmalloc(sizeof(readonlyCommandTable));
-    memcpy(commandTable,readonlyCommandTable,sizeof(readonlyCommandTable));
-    qsort(commandTable,
-        sizeof(readonlyCommandTable)/sizeof(struct redisCommand),
-        sizeof(struct redisCommand),qsortRedisCommands);
+        retval = dictAdd(server.commands, sdsnew(c->name), c);
+        assert(retval == DICT_OK);
+    }

 }
 
 /* ====================== Commands lookup and execution ===================== */
 
 }
 
 /* ====================== Commands lookup and execution ===================== */
 

-struct redisCommand *lookupCommand(char *name) {
-    struct redisCommand tmp = {name,NULL,0,0,NULL,0,0,0};
-    return bsearch(
-        &tmp,
-        commandTable,
-        sizeof(readonlyCommandTable)/sizeof(struct redisCommand),
-        sizeof(struct redisCommand),
-        qsortRedisCommands);
+struct redisCommand *lookupCommand(sds name) {
+    return dictFetchValue(server.commands, name);
+}
+
+struct redisCommand *lookupCommandByCString(char *s) {
+    struct redisCommand *cmd;
+    sds name = sdsnew(s);
+
+    cmd = dictFetchValue(server.commands, name);
+    sdsfree(name);
+    return cmd;

 }
 
 /* Call() is the core of Redis execution of a command */
 }
 
 /* Call() is the core of Redis execution of a command */


@@ -893,10 +960,9 @@ int processCommand(redisClient *c) {
      * go through checking for replication and QUIT will cause trouble
      * when FORCE_REPLICATION is enabled and would be implemented in
      * a regular command proc. */
      * go through checking for replication and QUIT will cause trouble
      * when FORCE_REPLICATION is enabled and would be implemented in
      * a regular command proc. */

-    redisAssert(!(c->flags & REDIS_QUIT));

     if (!strcasecmp(c->argv[0]->ptr,"quit")) {
     if (!strcasecmp(c->argv[0]->ptr,"quit")) {

-        c->flags |= REDIS_QUIT;

         addReply(c,shared.ok);
         addReply(c,shared.ok);

+        c->flags |= REDIS_CLOSE_AFTER_REPLY;

         return REDIS_ERR;
     }
 
         return REDIS_ERR;
     }
 


@@ -942,6 +1008,23 @@ int processCommand(redisClient *c) {
         return REDIS_OK;
     }
 
         return REDIS_OK;
     }
 

+    /* Only allow INFO and SLAVEOF when slave-serve-stale-data is no and
+     * we are a slave with a broken link with master. */
+    if (server.masterhost && server.replstate != REDIS_REPL_CONNECTED &&
+        server.repl_serve_stale_data == 0 &&
+        cmd->proc != infoCommand && cmd->proc != slaveofCommand)
+    {
+        addReplyError(c,
+            "link with MASTER is down and slave-serve-stale-data is set to no");
+        return REDIS_OK;
+    }
+
+    /* Loading DB? Return an error if the command is not INFO */
+    if (server.loading && cmd->proc != infoCommand) {
+        addReply(c, shared.loadingerr);
+        return REDIS_OK;
+    }
+

     /* Exec the command */
     if (c->flags & REDIS_MULTI &&
         cmd->proc != execCommand && cmd->proc != discardCommand &&
     /* Exec the command */
     if (c->flags & REDIS_MULTI &&
         cmd->proc != execCommand && cmd->proc != discardCommand &&


@@ -950,8 +1033,8 @@ int processCommand(redisClient *c) {
         queueMultiCommand(c,cmd);
         addReply(c,shared.queued);
     } else {
         queueMultiCommand(c,cmd);
         addReply(c,shared.queued);
     } else {

-        if (server.vm_enabled && server.vm_max_threads > 0 &&
-            blockClientOnSwappedKeys(c,cmd)) return REDIS_ERR;
+        if (server.ds_enabled && blockClientOnSwappedKeys(c,cmd))
+            return REDIS_ERR;

         call(c,cmd);
     }
     return REDIS_OK;
         call(c,cmd);
     }
     return REDIS_OK;


@@ -969,11 +1052,12 @@ int prepareForShutdown() {
         kill(server.bgsavechildpid,SIGKILL);
         rdbRemoveTempFile(server.bgsavechildpid);
     }
         kill(server.bgsavechildpid,SIGKILL);
         rdbRemoveTempFile(server.bgsavechildpid);
     }

-    if (server.appendonly) {
+    if (server.ds_enabled) {
+        /* FIXME: flush all objects on disk */
+    } else if (server.appendonly) {

         /* Append only file: fsync() the AOF and exit */
         aof_fsync(server.appendfd);
         /* Append only file: fsync() the AOF and exit */
         aof_fsync(server.appendfd);

-        if (server.vm_enabled) unlink(server.vm_swap_file);
-    } else {
+    } else if (server.saveparamslen > 0) {

         /* Snapshotting. Perform a SYNC SAVE and exit */
         if (rdbSave(server.dbfilename) != REDIS_OK) {
             /* Ooops.. error saving! The best we can do is to continue
         /* Snapshotting. Perform a SYNC SAVE and exit */
         if (rdbSave(server.dbfilename) != REDIS_OK) {
             /* Ooops.. error saving! The best we can do is to continue


@@ -984,6 +1068,8 @@ int prepareForShutdown() {
             redisLog(REDIS_WARNING,"Error trying to save the DB, can't exit");
             return REDIS_ERR;
         }
             redisLog(REDIS_WARNING,"Error trying to save the DB, can't exit");
             return REDIS_ERR;
         }

+    } else {
+        redisLog(REDIS_WARNING,"Not saving DB.");

     }
     if (server.daemonize) unlink(server.pidfile);
     redisLog(REDIS_WARNING,"Server exit now, bye bye...");
     }
     if (server.daemonize) unlink(server.pidfile);
     redisLog(REDIS_WARNING,"Server exit now, bye bye...");


@@ -1007,7 +1093,6 @@ void pingCommand(redisClient *c) {
 }
 
 void echoCommand(redisClient *c) {
 }
 
 void echoCommand(redisClient *c) {

-    c->argv[1] = tryObjectEncoding(c->argv[1]);

     addReplyBulk(c,c->argv[1]);
 }
 
     addReplyBulk(c,c->argv[1]);
 }
 


@@ -1055,6 +1140,7 @@ sds genRedisInfoString(void) {
         "process_id:%ld\r\n"
         "uptime_in_seconds:%ld\r\n"
         "uptime_in_days:%ld\r\n"
         "process_id:%ld\r\n"
         "uptime_in_seconds:%ld\r\n"
         "uptime_in_days:%ld\r\n"

+        "lru_clock:%ld\r\n"

         "used_cpu_sys:%.2f\r\n"
         "used_cpu_user:%.2f\r\n"
         "used_cpu_sys_childrens:%.2f\r\n"
         "used_cpu_sys:%.2f\r\n"
         "used_cpu_user:%.2f\r\n"
         "used_cpu_sys_childrens:%.2f\r\n"


@@ -1064,7 +1150,11 @@ sds genRedisInfoString(void) {
         "blocked_clients:%d\r\n"
         "used_memory:%zu\r\n"
         "used_memory_human:%s\r\n"
         "blocked_clients:%d\r\n"
         "used_memory:%zu\r\n"
         "used_memory_human:%s\r\n"

+        "used_memory_rss:%zu\r\n"

         "mem_fragmentation_ratio:%.2f\r\n"
         "mem_fragmentation_ratio:%.2f\r\n"

+        "use_tcmalloc:%d\r\n"
+        "loading:%d\r\n"
+        "aof_enabled:%d\r\n"

         "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"


@@ -1072,11 +1162,14 @@ sds genRedisInfoString(void) {
         "total_connections_received:%lld\r\n"
         "total_commands_processed:%lld\r\n"
         "expired_keys:%lld\r\n"
         "total_connections_received:%lld\r\n"
         "total_commands_processed:%lld\r\n"
         "expired_keys:%lld\r\n"

+        "evicted_keys:%lld\r\n"
+        "keyspace_hits:%lld\r\n"
+        "keyspace_misses:%lld\r\n"

         "hash_max_zipmap_entries:%zu\r\n"
         "hash_max_zipmap_value:%zu\r\n"
         "pubsub_channels:%ld\r\n"
         "pubsub_patterns:%u\r\n"
         "hash_max_zipmap_entries:%zu\r\n"
         "hash_max_zipmap_value:%zu\r\n"
         "pubsub_channels:%ld\r\n"
         "pubsub_patterns:%u\r\n"

-        "vm_enabled:%d\r\n"
+        "ds_enabled:%d\r\n"

         "role:%s\r\n"
         ,REDIS_VERSION,
         redisGitSHA1(),
         "role:%s\r\n"
         ,REDIS_VERSION,
         redisGitSHA1(),


@@ -1086,16 +1179,25 @@ sds genRedisInfoString(void) {
         (long) getpid(),
         uptime,
         uptime/(3600*24),
         (long) getpid(),
         uptime,
         uptime/(3600*24),

+        (unsigned long) server.lruclock,

         (float)self_ru.ru_utime.tv_sec+(float)self_ru.ru_utime.tv_usec/1000000,
         (float)self_ru.ru_stime.tv_sec+(float)self_ru.ru_stime.tv_usec/1000000,
         (float)c_ru.ru_utime.tv_sec+(float)c_ru.ru_utime.tv_usec/1000000,
         (float)c_ru.ru_stime.tv_sec+(float)c_ru.ru_stime.tv_usec/1000000,
         listLength(server.clients)-listLength(server.slaves),
         listLength(server.slaves),
         (float)self_ru.ru_utime.tv_sec+(float)self_ru.ru_utime.tv_usec/1000000,
         (float)self_ru.ru_stime.tv_sec+(float)self_ru.ru_stime.tv_usec/1000000,
         (float)c_ru.ru_utime.tv_sec+(float)c_ru.ru_utime.tv_usec/1000000,
         (float)c_ru.ru_stime.tv_sec+(float)c_ru.ru_stime.tv_usec/1000000,
         listLength(server.clients)-listLength(server.slaves),
         listLength(server.slaves),

-        server.blpop_blocked_clients,
+        server.bpop_blocked_clients,

         zmalloc_used_memory(),
         hmem,
         zmalloc_used_memory(),
         hmem,

+        zmalloc_get_rss(),

         zmalloc_get_fragmentation_ratio(),
         zmalloc_get_fragmentation_ratio(),

+#ifdef USE_TCMALLOC
+        1,
+#else
+        0,
+#endif
+        server.loading,
+        server.appendonly,

         server.dirty,
         server.bgsavechildpid != -1,
         server.lastsave,
         server.dirty,
         server.bgsavechildpid != -1,
         server.lastsave,


@@ -1103,11 +1205,14 @@ sds genRedisInfoString(void) {
         server.stat_numconnections,
         server.stat_numcommands,
         server.stat_expiredkeys,
         server.stat_numconnections,
         server.stat_numcommands,
         server.stat_expiredkeys,

+        server.stat_evictedkeys,
+        server.stat_keyspace_hits,
+        server.stat_keyspace_misses,

         server.hash_max_zipmap_entries,
         server.hash_max_zipmap_value,
         dictSize(server.pubsub_channels),
         listLength(server.pubsub_patterns),
         server.hash_max_zipmap_entries,
         server.hash_max_zipmap_value,
         dictSize(server.pubsub_channels),
         listLength(server.pubsub_patterns),

-        server.vm_enabled != 0,
+        server.ds_enabled != 0,

         server.masterhost == NULL ? "master" : "slave"
     );
     if (server.masterhost) {
         server.masterhost == NULL ? "master" : "slave"
     );
     if (server.masterhost) {


@@ -1116,43 +1221,63 @@ sds genRedisInfoString(void) {
             "master_port:%d\r\n"
             "master_link_status:%s\r\n"
             "master_last_io_seconds_ago:%d\r\n"
             "master_port:%d\r\n"
             "master_link_status:%s\r\n"
             "master_last_io_seconds_ago:%d\r\n"

+            "master_sync_in_progress:%d\r\n"

             ,server.masterhost,
             server.masterport,
             (server.replstate == REDIS_REPL_CONNECTED) ?
                 "up" : "down",
             ,server.masterhost,
             server.masterport,
             (server.replstate == REDIS_REPL_CONNECTED) ?
                 "up" : "down",

-            server.master ? ((int)(time(NULL)-server.master->lastinteraction)) : -1
+            server.master ? ((int)(time(NULL)-server.master->lastinteraction)) : -1,
+            server.replstate == REDIS_REPL_TRANSFER

         );
         );

+
+        if (server.replstate == REDIS_REPL_TRANSFER) {
+            info = sdscatprintf(info,
+                "master_sync_left_bytes:%ld\r\n"
+                "master_sync_last_io_seconds_ago:%d\r\n"
+                ,(long)server.repl_transfer_left,
+                (int)(time(NULL)-server.repl_transfer_lastio)
+            );
+        }

     }
     }

-    if (server.vm_enabled) {
+    if (server.ds_enabled) {

         lockThreadedIO();
         info = sdscatprintf(info,
         lockThreadedIO();
         info = sdscatprintf(info,

-            "vm_conf_max_memory:%llu\r\n"
-            "vm_conf_page_size:%llu\r\n"
-            "vm_conf_pages:%llu\r\n"
-            "vm_stats_used_pages:%llu\r\n"
-            "vm_stats_swapped_objects:%llu\r\n"
-            "vm_stats_swappin_count:%llu\r\n"
-            "vm_stats_swappout_count:%llu\r\n"
-            "vm_stats_io_newjobs_len:%lu\r\n"
-            "vm_stats_io_processing_len:%lu\r\n"
-            "vm_stats_io_processed_len:%lu\r\n"
-            "vm_stats_io_active_threads:%lu\r\n"
-            "vm_stats_blocked_clients:%lu\r\n"
-            ,(unsigned long long) server.vm_max_memory,
-            (unsigned long long) server.vm_page_size,
-            (unsigned long long) server.vm_pages,
-            (unsigned long long) server.vm_stats_used_pages,
-            (unsigned long long) server.vm_stats_swapped_objects,
-            (unsigned long long) server.vm_stats_swapins,
-            (unsigned long long) server.vm_stats_swapouts,
-            (unsigned long) listLength(server.io_newjobs),
-            (unsigned long) listLength(server.io_processing),
-            (unsigned long) listLength(server.io_processed),
-            (unsigned long) server.io_active_threads,
-            (unsigned long) server.vm_blocked_clients
+            "cache_max_memory:%llu\r\n"
+            "cache_blocked_clients:%lu\r\n"
+            ,(unsigned long long) server.cache_max_memory,
+            (unsigned long) server.cache_blocked_clients

         );
         unlockThreadedIO();
     }
         );
         unlockThreadedIO();
     }

+    if (server.loading) {
+        double perc;
+        time_t eta, elapsed;
+        off_t remaining_bytes = server.loading_total_bytes-
+                                server.loading_loaded_bytes;
+
+        perc = ((double)server.loading_loaded_bytes /
+               server.loading_total_bytes) * 100;
+
+        elapsed = time(NULL)-server.loading_start_time;
+        if (elapsed == 0) {
+            eta = 1; /* A fake 1 second figure if we don't have enough info */
+        } else {
+            eta = (elapsed*remaining_bytes)/server.loading_loaded_bytes;
+        }
+
+        info = sdscatprintf(info,
+            "loading_start_time:%ld\r\n"
+            "loading_total_bytes:%llu\r\n"
+            "loading_loaded_bytes:%llu\r\n"
+            "loading_loaded_perc:%.2f\r\n"
+            "loading_eta_seconds:%ld\r\n"
+            ,(unsigned long) server.loading_start_time,
+            (unsigned long long) server.loading_total_bytes,
+            (unsigned long long) server.loading_loaded_bytes,
+            perc,
+            eta
+        );
+    }

     for (j = 0; j < server.dbnum; j++) {
         long long keys, vkeys;
 
     for (j = 0; j < server.dbnum; j++) {
         long long keys, vkeys;
 


@@ -1186,27 +1311,6 @@ void monitorCommand(redisClient *c) {
 
 /* ============================ Maxmemory directive  ======================== */
 
 
 /* ============================ Maxmemory directive  ======================== */
 

-/* Try to free one object form the pre-allocated objects free list.
- * This is useful under low mem conditions as by default we take 1 million
- * free objects allocated. On success REDIS_OK is returned, otherwise
- * REDIS_ERR. */
-int tryFreeOneObjectFromFreelist(void) {
-    robj *o;
-
-    if (server.vm_enabled) pthread_mutex_lock(&server.obj_freelist_mutex);
-    if (listLength(server.objfreelist)) {
-        listNode *head = listFirst(server.objfreelist);
-        o = listNodeValue(head);
-        listDelNode(server.objfreelist,head);
-        if (server.vm_enabled) pthread_mutex_unlock(&server.obj_freelist_mutex);
-        zfree(o);
-        return REDIS_OK;
-    } else {
-        if (server.vm_enabled) pthread_mutex_unlock(&server.obj_freelist_mutex);
-        return REDIS_ERR;
-    }
-}
-

 /* 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:
 /* 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:


@@ -1219,34 +1323,89 @@ int tryFreeOneObjectFromFreelist(void) {
  * memory usage.
  */
 void freeMemoryIfNeeded(void) {
  * memory usage.
  */
 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;
+

     while (server.maxmemory && zmalloc_used_memory() > server.maxmemory) {
         int j, k, freed = 0;
 
     while (server.maxmemory && zmalloc_used_memory() > server.maxmemory) {
         int j, k, freed = 0;
 

-        if (tryFreeOneObjectFromFreelist() == REDIS_OK) continue;

         for (j = 0; j < server.dbnum; j++) {
         for (j = 0; j < server.dbnum; j++) {

-            int minttl = -1;
-            sds minkey = NULL;
-            robj *keyobj = NULL;
+            long bestval = 0; /* just to prevent warning */
+            sds bestkey = NULL;

             struct dictEntry *de;
             struct dictEntry *de;

+            redisDb *db = server.db+j;
+            dict *dict;

 
 

-            if (dictSize(server.db[j].expires)) {
-                freed = 1;
-                /* From a sample of three keys drop the one nearest to
-                 * the natural expire */
-                for (k = 0; k < 3; k++) {
-                    time_t t;
-
-                    de = dictGetRandomKey(server.db[j].expires);
-                    t = (time_t) dictGetEntryVal(de);
-                    if (minttl == -1 || t < minttl) {
-                        minkey = dictGetEntryKey(de);
-                        minttl = t;
+            if (server.maxmemory_policy == REDIS_MAXMEMORY_ALLKEYS_LRU ||
+                server.maxmemory_policy == REDIS_MAXMEMORY_ALLKEYS_RANDOM)
+            {
+                dict = server.db[j].dict;
+            } else {
+                dict = server.db[j].expires;
+            }
+            if (dictSize(dict) == 0) continue;
+
+            /* volatile-random and allkeys-random policy */
+            if (server.maxmemory_policy == REDIS_MAXMEMORY_ALLKEYS_RANDOM ||
+                server.maxmemory_policy == REDIS_MAXMEMORY_VOLATILE_RANDOM)
+            {
+                de = dictGetRandomKey(dict);
+                bestkey = dictGetEntryKey(de);
+            }
+
+            /* volatile-lru and allkeys-lru policy */
+            else if (server.maxmemory_policy == REDIS_MAXMEMORY_ALLKEYS_LRU ||
+                server.maxmemory_policy == REDIS_MAXMEMORY_VOLATILE_LRU)
+            {
+                for (k = 0; k < server.maxmemory_samples; k++) {
+                    sds thiskey;
+                    long thisval;
+                    robj *o;
+
+                    de = dictGetRandomKey(dict);
+                    thiskey = dictGetEntryKey(de);
+                    /* When policy is volatile-lru we need an additonal lookup
+                     * to locate the real key, as dict is set to db->expires. */
+                    if (server.maxmemory_policy == REDIS_MAXMEMORY_VOLATILE_LRU)
+                        de = dictFind(db->dict, thiskey);
+                    o = dictGetEntryVal(de);
+                    thisval = estimateObjectIdleTime(o);
+
+                    /* Higher idle time is better candidate for deletion */
+                    if (bestkey == NULL || thisval > bestval) {
+                        bestkey = thiskey;
+                        bestval = thisval;

                     }
                 }
                     }
                 }

-                keyobj = createStringObject(minkey,sdslen(minkey));
-                dbDelete(server.db+j,keyobj);
-                server.stat_expiredkeys++;
+            }
+
+            /* volatile-ttl */
+            else if (server.maxmemory_policy == REDIS_MAXMEMORY_VOLATILE_TTL) {
+                for (k = 0; k < server.maxmemory_samples; k++) {
+                    sds thiskey;
+                    long thisval;
+
+                    de = dictGetRandomKey(dict);
+                    thiskey = dictGetEntryKey(de);
+                    thisval = (long) dictGetEntryVal(de);
+
+                    /* Expire sooner (minor expire unix timestamp) is better
+                     * candidate for deletion */
+                    if (bestkey == NULL || thisval < bestval) {
+                        bestkey = thiskey;
+                        bestval = thisval;
+                    }
+                }
+            }
+
+            /* Finally remove the selected key. */
+            if (bestkey) {
+                robj *keyobj = createStringObject(bestkey,sdslen(bestkey));
+                dbDelete(db,keyobj);
+                server.stat_evictedkeys++;

                 decrRefCount(keyobj);
                 decrRefCount(keyobj);

+                freed++;

             }
         }
         if (!freed) return; /* nothing to free... */
             }
         }
         if (!freed) return; /* nothing to free... */


@@ -1319,7 +1478,6 @@ int main(int argc, char **argv) {
     time_t start;
 
     initServerConfig();
     time_t start;
 
     initServerConfig();

-    sortCommandTable();

     if (argc == 2) {
         if (strcmp(argv[1], "-v") == 0 ||
             strcmp(argv[1], "--version") == 0) version();
     if (argc == 2) {
         if (strcmp(argv[1], "-v") == 0 ||
             strcmp(argv[1], "--version") == 0) version();


@@ -1339,14 +1497,19 @@ int main(int argc, char **argv) {
     linuxOvercommitMemoryWarning();
 #endif
     start = time(NULL);
     linuxOvercommitMemoryWarning();
 #endif
     start = time(NULL);

-    if (server.appendonly) {
+    if (server.ds_enabled) {
+        redisLog(REDIS_NOTICE,"DB not loaded (running with disk back end)");
+    } else if (server.appendonly) {

         if (loadAppendOnlyFile(server.appendfilename) == REDIS_OK)
             redisLog(REDIS_NOTICE,"DB loaded from append only file: %ld seconds",time(NULL)-start);
     } else {
         if (rdbLoad(server.dbfilename) == REDIS_OK)
             redisLog(REDIS_NOTICE,"DB loaded from disk: %ld seconds",time(NULL)-start);
     }
         if (loadAppendOnlyFile(server.appendfilename) == REDIS_OK)
             redisLog(REDIS_NOTICE,"DB loaded from append only file: %ld seconds",time(NULL)-start);
     } else {
         if (rdbLoad(server.dbfilename) == REDIS_OK)
             redisLog(REDIS_NOTICE,"DB loaded from disk: %ld seconds",time(NULL)-start);
     }

-    redisLog(REDIS_NOTICE,"The server is now ready to accept connections on port %d", server.port);
+    if (server.ipfd > 0)
+        redisLog(REDIS_NOTICE,"The server is now ready to accept connections on port %d", server.port);
+    if (server.sofd > 0)
+        redisLog(REDIS_NOTICE,"The server is now ready to accept connections at %s", server.unixsocket);

     aeSetBeforeSleepProc(server.el,beforeSleep);
     aeMain(server.el);
     aeDeleteEventLoop(server.el);
     aeSetBeforeSleepProc(server.el,beforeSleep);
     aeMain(server.el);
     aeDeleteEventLoop(server.el);


@@ -1390,6 +1553,7 @@ void segvHandler(int sig, siginfo_t *info, void *secret) {
     int i, trace_size = 0;
     ucontext_t *uc = (ucontext_t*) secret;
     sds infostring;
     int i, trace_size = 0;
     ucontext_t *uc = (ucontext_t*) secret;
     sds infostring;

+    struct sigaction act;

     REDIS_NOTUSED(info);
 
     redisLog(REDIS_WARNING,
     REDIS_NOTUSED(info);
 
     redisLog(REDIS_WARNING,


@@ -1411,7 +1575,16 @@ void segvHandler(int sig, siginfo_t *info, void *secret) {
 
     /* free(messages); Don't call free() with possibly corrupted memory. */
     if (server.daemonize) unlink(server.pidfile);
 
     /* free(messages); Don't call free() with possibly corrupted memory. */
     if (server.daemonize) unlink(server.pidfile);

-    _exit(0);
+
+    /* Make sure we exit with the right signal at the end. So for instance
+     * the core will be dumped if enabled. */
+    sigemptyset (&act.sa_mask);
+    /* When the SA_SIGINFO flag is set in sa_flags then sa_sigaction
+     * is used. Otherwise, sa_handler is used */
+    act.sa_flags = SA_NODEFER | SA_ONSTACK | SA_RESETHAND;
+    act.sa_handler = SIG_DFL;
+    sigaction (sig, &act, NULL);
+    kill(getpid(),sig);

 }
 
 void sigtermHandler(int sig) {
 }
 
 void sigtermHandler(int sig) {