X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/1dd10ca233a533928ec2ff83f675499e4e7c1ff1..da47440d444cfe023f339e0f7d6056101a332a48:/src/redis.c diff --git a/src/redis.c b/src/redis.c index 27a855d9..ab79e9da 100644 --- a/src/redis.c +++ b/src/redis.c @@ -478,6 +478,10 @@ 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++; @@ -490,19 +494,19 @@ 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); - /* 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. */ @@ -733,6 +737,8 @@ void initServerConfig() { server.maxclients = 0; server.blpop_blocked_clients = 0; server.maxmemory = 0; + server.maxmemory_policy = REDIS_MAXMEMORY_VOLATILE_LRU; + server.maxmemory_samples = 3; server.vm_enabled = 0; server.vm_swap_file = zstrdup("/tmp/redis-%p.vm"); server.vm_page_size = 256; /* 256 bytes per page */ @@ -747,6 +753,7 @@ void initServerConfig() { 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 */ @@ -816,6 +823,8 @@ void initServer() { server.stat_numconnections = 0; server.stat_expiredkeys = 0; 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); if (aeCreateFileEvent(server.el, server.fd, AE_READABLE, @@ -1084,7 +1093,7 @@ int prepareForShutdown() { /* 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 @@ -1095,6 +1104,8 @@ int prepareForShutdown() { 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..."); @@ -1165,6 +1176,7 @@ sds genRedisInfoString(void) { "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" @@ -1175,6 +1187,7 @@ sds genRedisInfoString(void) { "used_memory:%zu\r\n" "used_memory_human:%s\r\n" "mem_fragmentation_ratio:%.2f\r\n" + "use_tcmalloc:%d\r\n" "changes_since_last_save:%lld\r\n" "bgsave_in_progress:%d\r\n" "last_save_time:%ld\r\n" @@ -1182,6 +1195,8 @@ sds genRedisInfoString(void) { "total_connections_received:%lld\r\n" "total_commands_processed:%lld\r\n" "expired_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" @@ -1196,6 +1211,7 @@ sds genRedisInfoString(void) { (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, @@ -1206,6 +1222,11 @@ sds genRedisInfoString(void) { zmalloc_used_memory(), hmem, zmalloc_get_fragmentation_ratio(), +#ifdef USE_TCMALLOC + 1, +#else + 0, +#endif server.dirty, server.bgsavechildpid != -1, server.lastsave, @@ -1213,6 +1234,8 @@ sds genRedisInfoString(void) { server.stat_numconnections, server.stat_numcommands, server.stat_expiredkeys, + server.stat_keyspace_hits, + server.stat_keyspace_misses, server.hash_max_zipmap_entries, server.hash_max_zipmap_value, dictSize(server.pubsub_channels), @@ -1329,10 +1352,93 @@ int tryFreeOneObjectFromFreelist(void) { * memory usage. */ void freeMemoryIfNeeded(void) { + /* Remove keys accordingly to the active policy as long as we are + * over the memory limit. */ while (server.maxmemory && zmalloc_used_memory() > server.maxmemory) { int j, k, freed = 0; + /* Basic strategy -- remove objects from the free list. */ if (tryFreeOneObjectFromFreelist() == REDIS_OK) continue; + + for (j = 0; j < server.dbnum; j++) { + long bestval; + sds bestkey = NULL; + struct dictEntry *de; + redisDb *db = server.db+j; + dict *dict; + + 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); + o = dictGetEntryVal(de); + thisval = estimateObjectIdleTime(o); + + /* Higher idle time is better candidate for deletion */ + if (bestkey == NULL || thisval > bestval) { + bestkey = thiskey; + bestval = thisval; + } + } + } + + /* 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_expiredkeys++; + decrRefCount(keyobj); + freed++; + } + } + if (!freed) return; /* nothing to free... */ + } + + while(0) { + int j, k, freed = 0; for (j = 0; j < server.dbnum; j++) { int minttl = -1; sds minkey = NULL; @@ -1500,6 +1606,7 @@ void segvHandler(int sig, siginfo_t *info, void *secret) { int i, trace_size = 0; ucontext_t *uc = (ucontext_t*) secret; sds infostring; + struct sigaction act; REDIS_NOTUSED(info); redisLog(REDIS_WARNING, @@ -1521,7 +1628,16 @@ 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); - _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) {