X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/f2b8ab346abd82d76a749a582396b053928e57af..20f5b3886761a0ba963fee435bba90dd09bd5bd5:/redis.c diff --git a/redis.c b/redis.c index e427ab60..74651d6f 100644 --- a/redis.c +++ b/redis.c @@ -59,6 +59,7 @@ #include #include #include +#include #if defined(__sun) #include "solarisfixes.h" @@ -162,6 +163,7 @@ * Check vmFindContiguousPages() to know more about this magic numbers. */ #define REDIS_VM_MAX_NEAR_PAGES 65536 #define REDIS_VM_MAX_RANDOM_JUMP 4096 +#define REDIS_VM_MAX_THREADS 32 /* Client flags */ #define REDIS_CLOSE 1 /* This client connection should be closed ASAP */ @@ -170,6 +172,7 @@ #define REDIS_MONITOR 8 /* This client is a slave monitor, see MONITOR */ #define REDIS_MULTI 16 /* This client is in a MULTI context */ #define REDIS_BLOCKED 32 /* The client is waiting in a blocking operation */ +#define REDIS_IO_WAIT 64 /* The client is waiting for Virtual Memory I/O */ /* Slave replication state - slave side */ #define REDIS_REPL_NONE 0 /* No active replication */ @@ -197,8 +200,9 @@ /* Log levels */ #define REDIS_DEBUG 0 -#define REDIS_NOTICE 1 -#define REDIS_WARNING 2 +#define REDIS_VERBOSE 1 +#define REDIS_NOTICE 2 +#define REDIS_WARNING 3 /* Anti-warning macro... */ #define REDIS_NOTUSED(V) ((void) V) @@ -302,6 +306,8 @@ typedef struct redisClient { int blockingkeysnum; /* Number of blocking keys */ time_t blockingto; /* Blocking operation timeout. If UNIX current time * is >= blockingto then the operation timed out. */ + list *io_keys; /* Keys this client is waiting to be loaded from the + * swap file in order to continue. */ } redisClient; struct saveparam { @@ -380,6 +386,29 @@ struct redisServer { off_t vm_near_pages; /* Number of pages allocated sequentially */ unsigned char *vm_bitmap; /* Bitmap of free/used pages */ time_t unixtime; /* Unix time sampled every second. */ + /* Virtual memory I/O threads stuff */ + /* An I/O thread process an element taken from the io_jobs queue and + * put the result of the operation in the io_done list. While the + * job is being processed, it's put on io_processing queue. */ + list *io_newjobs; /* List of VM I/O jobs yet to be processed */ + list *io_processing; /* List of VM I/O jobs being processed */ + list *io_processed; /* List of VM I/O jobs already processed */ + list *io_clients; /* All the clients waiting for SWAP I/O operations */ + pthread_mutex_t io_mutex; /* lock to access io_jobs/io_done/io_thread_job */ + int io_active_threads; /* Number of running I/O threads */ + int vm_max_threads; /* Max number of I/O threads running at the same time */ + /* Our main thread is blocked on the event loop, locking for sockets ready + * to be read or written, so when a threaded I/O operation is ready to be + * processed by the main thread, the I/O thread will use a unix pipe to + * awake the main thread. The followings are the two pipe FDs. */ + int io_ready_pipe_read; + int io_ready_pipe_write; + /* Virtual memory stats */ + unsigned long long vm_stats_used_pages; + unsigned long long vm_stats_swapped_objects; + unsigned long long vm_stats_swapouts; + unsigned long long vm_stats_swapins; + FILE *devnull; }; typedef void redisCommandProc(redisClient *c); @@ -445,6 +474,22 @@ struct sharedObjectsStruct { static double R_Zero, R_PosInf, R_NegInf, R_Nan; +/* VM threaded I/O request message */ +#define REDIS_IOJOB_LOAD 0 /* Load from disk to memory */ +#define REDIS_IOJOB_PREPARE_SWAP 1 /* Compute needed pages */ +#define REDIS_IOJOB_DO_SWAP 2 /* Swap from memory to disk */ +typedef struct iojon { + int type; /* Request type, REDIS_IOJOB_* */ + redisDb *db;/* Redis database */ + robj *key; /* This I/O request is about swapping this key */ + robj *val; /* the value to swap for REDIS_IOREQ_*_SWAP, otherwise this + * field is populated by the I/O thread for REDIS_IOREQ_LOAD. */ + off_t page; /* Swap page where to read/write the object */ + off_t pages; /* Swap pages needed to safe object. PREPARE_SWAP return val */ + int canceled; /* True if this command was canceled by blocking side of VM */ + pthread_t thread; /* ID of the thread processing this entry */ +} iojob; + /*================================ Prototypes =============================== */ static void freeStringObject(robj *o); @@ -494,8 +539,18 @@ static void vmInit(void); static void vmMarkPagesFree(off_t page, off_t count); static robj *vmLoadObject(robj *key); static robj *vmPreviewObject(robj *key); -static int vmSwapOneObject(void); +static int vmSwapOneObjectBlocking(void); +static int vmSwapOneObjectThreaded(void); static int vmCanSwapOut(void); +static void freeOneObjectFromFreelist(void); +static void acceptHandler(aeEventLoop *el, int fd, void *privdata, int mask); +static void vmThreadedIOCompletedJob(aeEventLoop *el, int fd, void *privdata, int mask); +static void vmCancelThreadedIOJob(robj *o); +static void lockThreadedIO(void); +static void unlockThreadedIO(void); +static int vmSwapObjectThreaded(robj *key, robj *val, redisDb *db); +static void freeIOJob(iojob *j); +static void queueIOJob(iojob *j); static void authCommand(redisClient *c); static void pingCommand(redisClient *c); @@ -949,7 +1004,7 @@ static void closeTimedoutClients(void) { !(c->flags & REDIS_MASTER) && /* no timeout for masters */ (now - c->lastinteraction > server.maxidletime)) { - redisLog(REDIS_DEBUG,"Closing idle client"); + redisLog(REDIS_VERBOSE,"Closing idle client"); freeClient(c); } else if (c->flags & REDIS_BLOCKED) { if (c->blockingto != 0 && c->blockingto < now) { @@ -976,9 +1031,9 @@ static void tryResizeHashTables(void) { for (j = 0; j < server.dbnum; j++) { if (htNeedsResize(server.db[j].dict)) { - redisLog(REDIS_DEBUG,"The hash table %d is too sparse, resize it...",j); + redisLog(REDIS_VERBOSE,"The hash table %d is too sparse, resize it...",j); dictResize(server.db[j].dict); - redisLog(REDIS_DEBUG,"Hash table %d resized.",j); + redisLog(REDIS_VERBOSE,"Hash table %d resized.",j); } if (htNeedsResize(server.db[j].expires)) dictResize(server.db[j].expires); @@ -1092,7 +1147,7 @@ static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientD used = dictSize(server.db[j].dict); vkeys = dictSize(server.db[j].expires); if (!(loops % 5) && (used || vkeys)) { - redisLog(REDIS_DEBUG,"DB %d: %lld keys (%lld volatile) in %lld slots HT.",j,used,vkeys,size); + redisLog(REDIS_VERBOSE,"DB %d: %lld keys (%lld volatile) in %lld slots HT.",j,used,vkeys,size); /* dictPrintStats(server.dict); */ } } @@ -1107,7 +1162,7 @@ static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientD /* Show information about connected clients */ if (!(loops % 5)) { - redisLog(REDIS_DEBUG,"%d clients connected (%d slaves), %zu bytes in use, %d shared objects", + redisLog(REDIS_VERBOSE,"%d clients connected (%d slaves), %zu bytes in use, %d shared objects", listLength(server.clients)-listLength(server.slaves), listLength(server.slaves), server.usedmemory, @@ -1179,15 +1234,24 @@ static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientD } /* Swap a few keys on disk if we are over the memory limit and VM - * is enbled. */ + * is enbled. Try to free objects from the free list first. */ if (vmCanSwapOut()) { while (server.vm_enabled && zmalloc_used_memory() > - server.vm_max_memory) { - if (vmSwapOneObject() == REDIS_ERR) { - if (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!"); + server.vm_max_memory) + { + if (listLength(server.objfreelist)) { + freeOneObjectFromFreelist(); + } else { + if (vmSwapOneObjectThreaded() == REDIS_ERR) { + if ((loops % 30) == 0 && 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 we freed just one object, because anyway when + * the I/O thread in charge to swap this object out will + * do its work, the handler of completed jobs will try to swap + * more objects if we are out of memory. */ break; } } @@ -1256,7 +1320,7 @@ static void resetServerSaveParams() { static void initServerConfig() { server.dbnum = REDIS_DEFAULT_DBNUM; server.port = REDIS_SERVERPORT; - server.verbosity = REDIS_DEBUG; + server.verbosity = REDIS_VERBOSE; server.maxidletime = REDIS_MAXIDLETIME; server.saveparams = NULL; server.logfile = NULL; /* NULL = log on standard output */ @@ -1282,6 +1346,7 @@ static void initServerConfig() { 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; resetServerSaveParams(); @@ -1310,6 +1375,11 @@ static void initServer() { signal(SIGPIPE, SIG_IGN); setupSigSegvAction(); + server.devnull = fopen("/dev/null","w"); + if (server.devnull == NULL) { + redisLog(REDIS_WARNING, "Can't open /dev/null: %s", server.neterr); + exit(1); + } server.clients = listCreate(); server.slaves = listCreate(); server.monitors = listCreate(); @@ -1341,6 +1411,8 @@ static void initServer() { server.stat_starttime = time(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.appendonly) { server.appendfd = open(server.appendfilename,O_WRONLY|O_APPEND|O_CREAT,0644); @@ -1436,6 +1508,7 @@ static void loadServerConfig(char *filename) { } } else if (!strcasecmp(argv[0],"loglevel") && argc == 2) { if (!strcasecmp(argv[1],"debug")) server.verbosity = REDIS_DEBUG; + else if (!strcasecmp(argv[1],"verbose")) server.verbosity = REDIS_VERBOSE; else if (!strcasecmp(argv[1],"notice")) server.verbosity = REDIS_NOTICE; else if (!strcasecmp(argv[1],"warning")) server.verbosity = REDIS_WARNING; else { @@ -1528,6 +1601,8 @@ static void loadServerConfig(char *filename) { server.vm_page_size = strtoll(argv[1], NULL, 10); } else if (!strcasecmp(argv[0],"vm-pages") && argc == 2) { server.vm_pages = strtoll(argv[1], NULL, 10); + } else if (!strcasecmp(argv[0],"vm-max-threads") && argc == 2) { + server.vm_max_threads = strtoll(argv[1], NULL, 10); } else { err = "Bad directive or wrong number of arguments"; goto loaderr; } @@ -1576,9 +1651,18 @@ static void freeClient(redisClient *c) { listRelease(c->reply); freeClientArgv(c); close(c->fd); + /* Remove from the list of clients */ ln = listSearchKey(server.clients,c); redisAssert(ln != NULL); listDelNode(server.clients,ln); + /* Remove from the list of clients waiting for VM operations */ + if (server.vm_enabled && listLength(c->io_keys)) { + ln = listSearchKey(server.io_clients,c); + if (ln) listDelNode(server.io_clients,ln); + listRelease(c->io_keys); + } + listRelease(c->io_keys); + /* Other cleanup */ if (c->flags & REDIS_SLAVE) { if (c->replstate == REDIS_REPL_SEND_BULK && c->repldbfd != -1) close(c->repldbfd); @@ -1677,7 +1761,7 @@ static void sendReplyToClient(aeEventLoop *el, int fd, void *privdata, int mask) if (errno == EAGAIN) { nwritten = 0; } else { - redisLog(REDIS_DEBUG, + redisLog(REDIS_VERBOSE, "Error writing to client: %s", strerror(errno)); freeClient(c); return; @@ -1730,7 +1814,7 @@ static void sendReplyToClientWritev(aeEventLoop *el, int fd, void *privdata, int /* write all collected blocks at once */ if((nwritten = writev(fd, iov, ion)) < 0) { if (errno != EAGAIN) { - redisLog(REDIS_DEBUG, + redisLog(REDIS_VERBOSE, "Error writing to client: %s", strerror(errno)); freeClient(c); return; @@ -2042,7 +2126,7 @@ again: * would not be called at all, but after the execution of the first commands * in the input buffer the client may be blocked, and the "goto again" * will try to reiterate. The following line will make it return asap. */ - if (c->flags & REDIS_BLOCKED) return; + if (c->flags & REDIS_BLOCKED || c->flags & REDIS_IO_WAIT) return; if (c->bulklen == -1) { /* Read the first line of the query */ char *p = strchr(c->querybuf,'\n'); @@ -2091,7 +2175,7 @@ again: } return; } else if (sdslen(c->querybuf) >= REDIS_REQUEST_MAX_SIZE) { - redisLog(REDIS_DEBUG, "Client protocol error"); + redisLog(REDIS_VERBOSE, "Client protocol error"); freeClient(c); return; } @@ -2128,12 +2212,12 @@ static void readQueryFromClient(aeEventLoop *el, int fd, void *privdata, int mas if (errno == EAGAIN) { nread = 0; } else { - redisLog(REDIS_DEBUG, "Reading from client: %s",strerror(errno)); + redisLog(REDIS_VERBOSE, "Reading from client: %s",strerror(errno)); freeClient(c); return; } } else if (nread == 0) { - redisLog(REDIS_DEBUG, "Client closed connection"); + redisLog(REDIS_VERBOSE, "Client closed connection"); freeClient(c); return; } @@ -2179,10 +2263,12 @@ static redisClient *createClient(int fd) { c->authenticated = 0; c->replstate = REDIS_REPL_NONE; c->reply = listCreate(); - c->blockingkeys = NULL; - c->blockingkeysnum = 0; listSetFreeMethod(c->reply,decrRefCount); listSetDupMethod(c->reply,dupClientReplyValue); + c->blockingkeys = NULL; + c->blockingkeysnum = 0; + c->io_keys = listCreate(); + listSetFreeMethod(c->io_keys,decrRefCount); if (aeCreateFileEvent(server.el, c->fd, AE_READABLE, readQueryFromClient, c) == AE_ERR) { freeClient(c); @@ -2252,10 +2338,10 @@ static void acceptHandler(aeEventLoop *el, int fd, void *privdata, int mask) { cfd = anetAccept(server.neterr, fd, cip, &cport); if (cfd == AE_ERR) { - redisLog(REDIS_DEBUG,"Accepting client connection: %s", server.neterr); + redisLog(REDIS_VERBOSE,"Accepting client connection: %s", server.neterr); return; } - redisLog(REDIS_DEBUG,"Accepted %s:%d", cip, cport); + redisLog(REDIS_VERBOSE,"Accepted %s:%d", cip, cport); if ((c = createClient(cfd)) == NULL) { redisLog(REDIS_WARNING,"Error allocating resoures for the client"); close(cfd); /* May be already closed, just ingore errors */ @@ -2310,6 +2396,7 @@ static robj *createStringObject(char *ptr, size_t len) { } static robj *dupStringObject(robj *o) { + assert(o->encoding == REDIS_ENCODING_RAW); return createStringObject(o->ptr,sdslen(o->ptr)); } @@ -2367,19 +2454,27 @@ static void incrRefCount(robj *o) { static void decrRefCount(void *obj) { robj *o = obj; - /* REDIS_VM_SWAPPED */ - if (server.vm_enabled && o->storage == REDIS_VM_SWAPPED) { - redisAssert(o->refcount == 1); + /* Object is swapped out, or in the process of being loaded. */ + if (server.vm_enabled && + (o->storage == REDIS_VM_SWAPPED || o->storage == REDIS_VM_LOADING)) + { + if (o->storage == REDIS_VM_SWAPPED || o->storage == REDIS_VM_LOADING) { + redisAssert(o->refcount == 1); + } + if (o->storage == REDIS_VM_LOADING) vmCancelThreadedIOJob(obj); redisAssert(o->type == REDIS_STRING); freeStringObject(o); vmMarkPagesFree(o->vm.page,o->vm.usedpages); if (listLength(server.objfreelist) > REDIS_OBJFREELIST_MAX || !listAddNodeHead(server.objfreelist,o)) zfree(o); + server.vm_stats_swapped_objects--; return; } - /* REDIS_VM_MEMORY */ + /* Object is in memory, or in the process of being swapped out. */ if (--(o->refcount) == 0) { + if (server.vm_enabled && o->storage == REDIS_VM_SWAPPING) + vmCancelThreadedIOJob(obj); switch(o->type) { case REDIS_STRING: freeStringObject(o); break; case REDIS_LIST: freeListObject(o); break; @@ -2401,7 +2496,13 @@ static robj *lookupKey(redisDb *db, robj *key) { robj *val = dictGetEntryVal(de); if (server.vm_enabled) { - if (key->storage == REDIS_VM_MEMORY) { + if (key->storage == REDIS_VM_MEMORY || + key->storage == REDIS_VM_SWAPPING) + { + /* If we were swapping the object out, stop it, this key + * was requested. */ + if (key->storage == REDIS_VM_SWAPPING) + vmCancelThreadedIOJob(key); /* Update the access time of the key for the aging algorithm. */ key->vm.atime = server.unixtime; } else { @@ -2737,9 +2838,23 @@ static int rdbSaveStringObjectRaw(FILE *fp, robj *obj) { static int rdbSaveStringObject(FILE *fp, robj *obj) { int retval; - obj = getDecodedObject(obj); - retval = rdbSaveStringObjectRaw(fp,obj); - decrRefCount(obj); + if (obj->storage == REDIS_VM_MEMORY && + obj->encoding != REDIS_ENCODING_RAW) + { + obj = getDecodedObject(obj); + retval = rdbSaveStringObjectRaw(fp,obj); + decrRefCount(obj); + } else { + /* This is a fast path when we are sure the object is not encoded. + * Note that's any *faster* actually as we needed to add the conditional + * but because this may happen in a background process we don't want + * to touch the object fields with incr/decrRefCount in order to + * preveny copy on write of pages. + * + * Also incrRefCount() will have a failing assert() if we try to call + * it against an object with storage != REDIS_VM_MEMORY. */ + retval = rdbSaveStringObjectRaw(fp,obj); + } return retval; } @@ -2825,20 +2940,16 @@ static int rdbSaveObject(FILE *fp, robj *o) { * the rdbSaveObject() function. Currently we use a trick to get * this length with very little changes to the code. In the future * we could switch to a faster solution. */ -static off_t rdbSavedObjectLen(robj *o) { - static FILE *fp = NULL; - - if (fp == NULL) fp = fopen("/dev/null","w"); - assert(fp != NULL); - +static off_t rdbSavedObjectLen(robj *o, FILE *fp) { + if (fp == NULL) fp = server.devnull; rewind(fp); assert(rdbSaveObject(fp,o) != 1); return ftello(fp); } /* Return the number of pages required to save this object in the swap file */ -static off_t rdbSavedObjectPages(robj *o) { - off_t bytes = rdbSavedObjectLen(o); +static off_t rdbSavedObjectPages(robj *o, FILE *fp) { + off_t bytes = rdbSavedObjectLen(o,fp); return (bytes+(server.vm_page_size-1))/server.vm_page_size; } @@ -2888,25 +2999,23 @@ static int rdbSave(char *filename) { } /* Save the key and associated value. This requires special * handling if the value is swapped out. */ - if (key->storage == REDIS_VM_MEMORY) { + if (!server.vm_enabled || key->storage == REDIS_VM_MEMORY || + key->storage == REDIS_VM_SWAPPING) { /* Save type, key, value */ if (rdbSaveType(fp,o->type) == -1) goto werr; if (rdbSaveStringObject(fp,key) == -1) goto werr; if (rdbSaveObject(fp,o) == -1) goto werr; } else { - robj *po, *newkey; + /* REDIS_VM_SWAPPED or REDIS_VM_LOADING */ + robj *po; /* Get a preview of the object in memory */ po = vmPreviewObject(key); - /* Also duplicate the key object, to pass around a standard - * string object. */ - newkey = dupStringObject(key); /* Save type, key, value */ if (rdbSaveType(fp,key->vtype) == -1) goto werr; - if (rdbSaveStringObject(fp,newkey) == -1) goto werr; + if (rdbSaveStringObject(fp,key) == -1) goto werr; if (rdbSaveObject(fp,po) == -1) goto werr; /* Remove the loaded object from memory */ decrRefCount(po); - decrRefCount(newkey); } } dictReleaseIterator(di); @@ -3166,6 +3275,7 @@ static int rdbLoad(char *filename) { redisDb *db = server.db+0; char buf[1024]; time_t expiretime = -1, now = time(NULL); + long long loadedkeys = 0; fp = fopen(filename,"r"); if (!fp) return REDIS_ERR; @@ -3223,6 +3333,13 @@ static int rdbLoad(char *filename) { expiretime = -1; } keyobj = o = NULL; + /* Handle swapping while loading big datasets when VM is on */ + loadedkeys++; + if (server.vm_enabled && (loadedkeys % 5000) == 0) { + while (zmalloc_used_memory() > server.vm_max_memory) { + if (vmSwapOneObjectBlocking() == REDIS_ERR) break; + } + } } fclose(fp); return REDIS_OK; @@ -5387,6 +5504,27 @@ static void sortCommand(redisClient *c) { zfree(vector); } +/* Convert an amount of bytes into a human readable string in the form + * of 100B, 2G, 100M, 4K, and so forth. */ +static void bytesToHuman(char *s, unsigned long long n) { + double d; + + if (n < 1024) { + /* Bytes */ + sprintf(s,"%lluB",n); + return; + } else if (n < (1024*1024)) { + d = (double)n/(1024); + sprintf(s,"%.2fK",d); + } else if (n < (1024LL*1024*1024)) { + d = (double)n/(1024*1024); + sprintf(s,"%.2fM",d); + } else if (n < (1024LL*1024*1024*1024)) { + d = (double)n/(1024LL*1024*1024); + sprintf(s,"%.2fM",d); + } +} + /* Create the string returned by the INFO command. This is decoupled * by the INFO command itself as we need to report the same information * on memory corruption problems. */ @@ -5394,39 +5532,47 @@ static sds genRedisInfoString(void) { sds info; time_t uptime = time(NULL)-server.stat_starttime; int j; - + char hmem[64]; + + bytesToHuman(hmem,server.usedmemory); info = sdscatprintf(sdsempty(), "redis_version:%s\r\n" "arch_bits:%s\r\n" "multiplexing_api:%s\r\n" + "process_id:%ld\r\n" "uptime_in_seconds:%ld\r\n" "uptime_in_days:%ld\r\n" "connected_clients:%d\r\n" "connected_slaves:%d\r\n" "blocked_clients:%d\r\n" "used_memory:%zu\r\n" + "used_memory_human:%s\r\n" "changes_since_last_save:%lld\r\n" "bgsave_in_progress:%d\r\n" "last_save_time:%ld\r\n" "bgrewriteaof_in_progress:%d\r\n" "total_connections_received:%lld\r\n" "total_commands_processed:%lld\r\n" + "vm_enabled:%d\r\n" "role:%s\r\n" ,REDIS_VERSION, (sizeof(long) == 8) ? "64" : "32", aeGetApiName(), + (long) getpid(), uptime, uptime/(3600*24), listLength(server.clients)-listLength(server.slaves), listLength(server.slaves), server.blockedclients, server.usedmemory, + hmem, server.dirty, server.bgsavechildpid != -1, server.lastsave, server.bgrewritechildpid != -1, server.stat_numconnections, server.stat_numcommands, + server.vm_enabled != 0, server.masterhost == NULL ? "master" : "slave" ); if (server.masterhost) { @@ -5442,6 +5588,32 @@ static sds genRedisInfoString(void) { server.master ? ((int)(time(NULL)-server.master->lastinteraction)) : -1 ); } + if (server.vm_enabled) { + 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_waiting_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) listLength(server.io_clients) + ); + } for (j = 0; j < server.dbnum; j++) { long long keys, vkeys; @@ -6002,7 +6174,7 @@ static void sendBulkToSlave(aeEventLoop *el, int fd, void *privdata, int mask) { return; } if ((nwritten = write(fd,buf,buflen)) == -1) { - redisLog(REDIS_DEBUG,"Write error sending DB to slave: %s", + redisLog(REDIS_VERBOSE,"Write error sending DB to slave: %s", strerror(errno)); freeClient(slave); return; @@ -6206,6 +6378,18 @@ static void slaveofCommand(redisClient *c) { /* ============================ Maxmemory directive ======================== */ +/* 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. */ +static void freeOneObjectFromFreelist(void) { + robj *o; + + listNode *head = listFirst(server.objfreelist); + o = listNodeValue(head); + listDelNode(server.objfreelist,head); + zfree(o); +} + /* 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: @@ -6220,12 +6404,7 @@ static void slaveofCommand(redisClient *c) { static void freeMemoryIfNeeded(void) { while (server.maxmemory && zmalloc_used_memory() > server.maxmemory) { if (listLength(server.objfreelist)) { - robj *o; - - listNode *head = listFirst(server.objfreelist); - o = listNodeValue(head); - listDelNode(server.objfreelist,head); - zfree(o); + freeOneObjectFromFreelist(); } else { int j, k, freed = 0; @@ -6376,6 +6555,7 @@ int loadAppendOnlyFile(char *filename) { struct redisClient *fakeClient; FILE *fp = fopen(filename,"r"); struct redis_stat sb; + unsigned long long loadedkeys = 0; if (redis_fstat(fileno(fp),&sb) != -1 && sb.st_size == 0) return REDIS_ERR; @@ -6437,6 +6617,13 @@ int loadAppendOnlyFile(char *filename) { /* Clean up, ready for the next command */ for (j = 0; j < argc; j++) decrRefCount(argv[j]); zfree(argv); + /* Handle swapping while loading big datasets when VM is on */ + loadedkeys++; + if (server.vm_enabled && (loadedkeys % 5000) == 0) { + while (zmalloc_used_memory() > server.vm_max_memory) { + if (vmSwapOneObjectBlocking() == REDIS_ERR) break; + } + } } fclose(fp); freeFakeClient(fakeClient); @@ -6457,16 +6644,21 @@ fmterr: /* Write an object into a file in the bulk format $\r\n\r\n */ static int fwriteBulk(FILE *fp, robj *obj) { char buf[128]; - obj = getDecodedObject(obj); + int decrrc = 0; + + if (obj->storage == REDIS_VM_MEMORY && obj->encoding != REDIS_ENCODING_RAW){ + obj = getDecodedObject(obj); + decrrc = 1; + } snprintf(buf,sizeof(buf),"$%ld\r\n",(long)sdslen(obj->ptr)); if (fwrite(buf,strlen(buf),1,fp) == 0) goto err; if (sdslen(obj->ptr) && fwrite(obj->ptr,sdslen(obj->ptr),1,fp) == 0) goto err; if (fwrite("\r\n",2,1,fp) == 0) goto err; - decrRefCount(obj); + if (decrrc) decrRefCount(obj); return 1; err: - decrRefCount(obj); + if (decrrc) decrRefCount(obj); return 0; } @@ -6532,12 +6724,16 @@ static int rewriteAppendOnlyFile(char *filename) { int swapped; key = dictGetEntryKey(de); - if (key->storage == REDIS_VM_MEMORY) { + /* If the value for this key is swapped, load a preview in memory. + * We use a "swapped" flag to remember if we need to free the + * value object instead to just increment the ref count anyway + * in order to avoid copy-on-write of pages if we are forked() */ + if (!server.vm_enabled || key->storage == REDIS_VM_MEMORY || + key->storage == REDIS_VM_SWAPPING) { o = dictGetEntryVal(de); swapped = 0; } else { o = vmPreviewObject(key); - key = dupStringObject(key); swapped = 1; } expiretime = getExpire(db,key); @@ -6608,12 +6804,7 @@ static int rewriteAppendOnlyFile(char *filename) { if (fwriteBulk(fp,key) == 0) goto werr; if (fwriteBulkLong(fp,expiretime) == 0) goto werr; } - /* We created a few temp objects if the key->value pair - * was about a swapped out object. Free both. */ - if (swapped) { - decrRefCount(key); - decrRefCount(o); - } + if (swapped) decrRefCount(o); } dictReleaseIterator(di); } @@ -6709,9 +6900,31 @@ static void aofRemoveTempFile(pid_t childpid) { unlink(tmpfile); } -/* =============================== Virtual Memory =========================== */ +/* Virtual Memory is composed mainly of two subsystems: + * - Blocking Virutal Memory + * - Threaded Virtual Memory I/O + * The two parts are not fully decoupled, but functions are split among two + * different sections of the source code (delimited by comments) in order to + * make more clear what functionality is about the blocking VM and what about + * the threaded (not blocking) VM. + * + * Redis VM design: + * + * Redis VM is a blocking VM (one that blocks reading swapped values from + * disk into memory when a value swapped out is needed in memory) that is made + * unblocking by trying to examine the command argument vector in order to + * load in background values that will likely be needed in order to exec + * the command. The command is executed only once all the relevant keys + * are loaded into memory. + * + * This basically is almost as simple of a blocking VM, but almost as parallel + * as a fully non-blocking VM. + */ + +/* =================== Virtual Memory - Blocking Side ====================== */ static void vmInit(void) { off_t totsize; + int pipefds[2]; server.vm_fp = fopen("/tmp/redisvm","w+b"); if (server.vm_fp == NULL) { @@ -6721,6 +6934,10 @@ static void vmInit(void) { server.vm_fd = fileno(server.vm_fp); server.vm_next_page = 0; server.vm_near_pages = 0; + server.vm_stats_used_pages = 0; + server.vm_stats_swapped_objects = 0; + server.vm_stats_swapouts = 0; + server.vm_stats_swapins = 0; totsize = server.vm_pages*server.vm_page_size; redisLog(REDIS_NOTICE,"Allocating %lld bytes of swap file",totsize); if (ftruncate(server.vm_fd,totsize) == -1) { @@ -6731,12 +6948,32 @@ static void vmInit(void) { redisLog(REDIS_NOTICE,"Swap file allocated with success"); } server.vm_bitmap = zmalloc((server.vm_pages+7)/8); - redisLog(REDIS_DEBUG,"Allocated %lld bytes page table for %lld pages", + redisLog(REDIS_VERBOSE,"Allocated %lld bytes page table for %lld pages", (long long) (server.vm_pages+7)/8, server.vm_pages); memset(server.vm_bitmap,0,(server.vm_pages+7)/8); /* Try to remove the swap file, so the OS will really delete it from the * file system when Redis exists. */ unlink("/tmp/redisvm"); + + /* Initialize threaded I/O (used by Virtual Memory) */ + server.io_newjobs = listCreate(); + server.io_processing = listCreate(); + server.io_processed = listCreate(); + server.io_clients = listCreate(); + pthread_mutex_init(&server.io_mutex,NULL); + server.io_active_threads = 0; + if (pipe(pipefds) == -1) { + redisLog(REDIS_WARNING,"Unable to intialized VM: pipe(2): %s. Exiting." + ,strerror(errno)); + exit(1); + } + server.io_ready_pipe_read = pipefds[0]; + server.io_ready_pipe_write = pipefds[1]; + redisAssert(anetNonBlock(NULL,server.io_ready_pipe_read) != ANET_ERR); + /* Listen for events in the threaded I/O pipe */ + if (aeCreateFileEvent(server.el, server.io_ready_pipe_read, AE_READABLE, + vmThreadedIOCompletedJob, NULL) == AE_ERR) + oom("creating file event"); } /* Mark the page as used */ @@ -6744,8 +6981,8 @@ static void vmMarkPageUsed(off_t page) { off_t byte = page/8; int bit = page&7; server.vm_bitmap[byte] |= 1<= server.vm_pages) { this -= server.vm_pages; @@ -6855,8 +7094,8 @@ static int vmFindContiguousPages(off_t *first, int n) { * needed to later retrieve the object into the key object. * If we can't find enough contiguous empty pages to swap the object on disk * REDIS_ERR is returned. */ -static int vmSwapObject(robj *key, robj *val) { - off_t pages = rdbSavedObjectPages(val); +static int vmSwapObjectBlocking(robj *key, robj *val) { + off_t pages = rdbSavedObjectPages(val,NULL); off_t page; assert(key->storage == REDIS_VM_MEMORY); @@ -6864,7 +7103,7 @@ static int vmSwapObject(robj *key, robj *val) { if (vmFindContiguousPages(&page,pages) == REDIS_ERR) return REDIS_ERR; if (fseeko(server.vm_fp,page*server.vm_page_size,SEEK_SET) == -1) { redisLog(REDIS_WARNING, - "Critical VM problem in vmSwapObject(): can't seek: %s", + "Critical VM problem in vmSwapObjectBlocking(): can't seek: %s", strerror(errno)); return REDIS_ERR; } @@ -6878,6 +7117,9 @@ static int vmSwapObject(robj *key, robj *val) { redisLog(REDIS_DEBUG,"VM: object %s swapped out at %lld (%lld pages)", (unsigned char*) key->ptr, (unsigned long long) page, (unsigned long long) pages); + server.vm_stats_swapped_objects++; + server.vm_stats_swapouts++; + fflush(server.vm_fp); return REDIS_OK; } @@ -6889,7 +7131,7 @@ static int vmSwapObject(robj *key, robj *val) { static robj *vmGenericLoadObject(robj *key, int preview) { robj *val; - assert(key->storage == REDIS_VM_SWAPPED); + redisAssert(key->storage == REDIS_VM_SWAPPED); if (fseeko(server.vm_fp,key->vm.page*server.vm_page_size,SEEK_SET) == -1) { redisLog(REDIS_WARNING, "Unrecoverable VM problem in vmLoadObject(): can't seek: %s", @@ -6907,12 +7149,21 @@ static robj *vmGenericLoadObject(robj *key, int preview) { vmMarkPagesFree(key->vm.page,key->vm.usedpages); redisLog(REDIS_DEBUG, "VM: object %s loaded from disk", (unsigned char*) key->ptr); + server.vm_stats_swapped_objects--; + } else { + redisLog(REDIS_DEBUG, "VM: object %s previewed from disk", + (unsigned char*) key->ptr); } + server.vm_stats_swapins++; return val; } /* Plain object loading, from swap to memory */ static robj *vmLoadObject(robj *key) { + /* If we are loading the object in background, stop it, we + * need to load this object synchronously ASAP. */ + if (key->storage == REDIS_VM_LOADING) + vmCancelThreadedIOJob(key); return vmGenericLoadObject(key,0); } @@ -6993,11 +7244,15 @@ static double computeObjectSwappability(robj *o) { /* Try to swap an object that's a good candidate for swapping. * Returns REDIS_OK if the object was swapped, REDIS_ERR if it's not possible - * to swap any object at all. */ -static int vmSwapOneObject(void) { + * to swap any object at all. + * + * If 'usethreaded' is true, Redis will try to swap the object in background + * using I/O threads. */ +static int vmSwapOneObject(int usethreads) { int j, i; struct dictEntry *best = NULL; double best_swappability = 0; + redisDb *best_db = NULL; robj *key, *val; for (j = 0; j < server.dbnum; j++) { @@ -7021,6 +7276,7 @@ static int vmSwapOneObject(void) { if (!best || swappability > best_swappability) { best = de; best_swappability = swappability; + best_db = db; } } } @@ -7041,14 +7297,27 @@ static int vmSwapOneObject(void) { key = dictGetEntryKey(best) = newkey; } /* Swap it */ - if (vmSwapObject(key,val) == REDIS_OK) { - dictGetEntryVal(best) = NULL; + if (usethreads) { + vmSwapObjectThreaded(key,val,best_db); return REDIS_OK; } else { - return REDIS_ERR; + if (vmSwapObjectBlocking(key,val) == REDIS_OK) { + dictGetEntryVal(best) = NULL; + return REDIS_OK; + } else { + return REDIS_ERR; + } } } +static int vmSwapOneObjectBlocking() { + return vmSwapOneObject(0); +} + +static int vmSwapOneObjectThreaded() { + return vmSwapOneObject(1); +} + /* Return true if it's safe to swap out objects in a given moment. * Basically we don't want to swap objects out while there is a BGSAVE * or a BGAEOREWRITE running in backgroud. */ @@ -7069,6 +7338,263 @@ static int deleteIfSwapped(redisDb *db, robj *key) { return 1; } +/* =================== Virtual Memory - Threaded I/O ======================= */ + +static void freeIOJob(iojob *j) { + if (j->type == REDIS_IOJOB_PREPARE_SWAP || + j->type == REDIS_IOJOB_DO_SWAP) + decrRefCount(j->val); + decrRefCount(j->key); + zfree(j); +} + +/* Every time a thread finished a Job, it writes a byte into the write side + * of an unix pipe in order to "awake" the main thread, and this function + * is called. */ +static void vmThreadedIOCompletedJob(aeEventLoop *el, int fd, void *privdata, + int mask) +{ + char buf[1]; + int retval; + REDIS_NOTUSED(el); + REDIS_NOTUSED(mask); + REDIS_NOTUSED(privdata); + + /* For every byte we read in the read side of the pipe, there is one + * I/O job completed to process. */ + while((retval = read(fd,buf,1)) == 1) { + iojob *j; + listNode *ln; + robj *key; + struct dictEntry *de; + + redisLog(REDIS_DEBUG,"Processing I/O completed job"); + assert(listLength(server.io_processed) != 0); + + /* Get the processed element (the oldest one) */ + lockThreadedIO(); + ln = listFirst(server.io_processed); + j = ln->value; + listDelNode(server.io_processed,ln); + unlockThreadedIO(); + /* If this job is marked as canceled, just ignore it */ + if (j->canceled) { + freeIOJob(j); + continue; + } + /* Post process it in the main thread, as there are things we + * can do just here to avoid race conditions and/or invasive locks */ + redisLog(REDIS_DEBUG,"Job type: %d, key at %p (%s) refcount: %d\n", j->type, (void*)j->key, (char*)j->key->ptr, j->key->refcount); + de = dictFind(j->db->dict,j->key); + assert(de != NULL); + key = dictGetEntryKey(de); + if (j->type == REDIS_IOJOB_LOAD) { + /* Key loaded, bring it at home */ + key->storage = REDIS_VM_MEMORY; + key->vm.atime = server.unixtime; + vmMarkPagesFree(key->vm.page,key->vm.usedpages); + redisLog(REDIS_DEBUG, "VM: object %s loaded from disk (threaded)", + (unsigned char*) key->ptr); + server.vm_stats_swapped_objects--; + server.vm_stats_swapins++; + freeIOJob(j); + } else if (j->type == REDIS_IOJOB_PREPARE_SWAP) { + /* Now we know the amount of pages required to swap this object. + * Let's find some space for it, and queue this task again + * rebranded as REDIS_IOJOB_DO_SWAP. */ + if (vmFindContiguousPages(&j->page,j->pages) == REDIS_ERR) { + /* Ooops... no space! */ + freeIOJob(j); + } else { + j->type = REDIS_IOJOB_DO_SWAP; + lockThreadedIO(); + queueIOJob(j); + unlockThreadedIO(); + } + } else if (j->type == REDIS_IOJOB_DO_SWAP) { + robj *val; + + /* Key swapped. We can finally free some memory. */ + val = dictGetEntryVal(de); + key->vm.page = j->page; + key->vm.usedpages = j->pages; + key->storage = REDIS_VM_SWAPPED; + key->vtype = j->val->type; + decrRefCount(val); /* Deallocate the object from memory. */ + dictGetEntryVal(de) = NULL; + vmMarkPagesUsed(j->page,j->pages); + redisLog(REDIS_DEBUG, + "VM: object %s swapped out at %lld (%lld pages) (threaded)", + (unsigned char*) key->ptr, + (unsigned long long) j->page, (unsigned long long) j->pages); + server.vm_stats_swapped_objects++; + server.vm_stats_swapouts++; + freeIOJob(j); + /* Put a few more swap requests in queue if we are still + * out of memory */ + if (zmalloc_used_memory() > server.vm_max_memory) { + int more = 1; + while(more) { + lockThreadedIO(); + more = listLength(server.io_newjobs) < + (unsigned) server.vm_max_threads; + unlockThreadedIO(); + /* Don't waste CPU time if swappable objects are rare. */ + if (vmSwapOneObjectThreaded() == REDIS_ERR) break; + } + } + } + } + if (retval < 0 && errno != EAGAIN) { + redisLog(REDIS_WARNING, + "WARNING: read(2) error in vmThreadedIOCompletedJob() %s", + strerror(errno)); + } +} + +static void lockThreadedIO(void) { + pthread_mutex_lock(&server.io_mutex); +} + +static void unlockThreadedIO(void) { + pthread_mutex_unlock(&server.io_mutex); +} + +/* Remove the specified object from the threaded I/O queue if still not + * processed, otherwise make sure to flag it as canceled. */ +static void vmCancelThreadedIOJob(robj *o) { + list *lists[3] = { + server.io_newjobs, server.io_processing, server.io_processed + }; + int i; + + assert(o->storage == REDIS_VM_LOADING || o->storage == REDIS_VM_SWAPPING); + lockThreadedIO(); + /* Search for a matching key in one of the queues */ + for (i = 0; i < 3; i++) { + listNode *ln; + + listRewind(lists[i]); + while ((ln = listYield(lists[i])) != NULL) { + iojob *job = ln->value; + + if (compareStringObjects(job->key,o) == 0) { + switch(i) { + case 0: /* io_newjobs */ + /* If the job was not yet processed the best thing to do + * is to remove it from the queue at all */ + decrRefCount(job->key); + if (job->type == REDIS_IOJOB_PREPARE_SWAP || + job->type == REDIS_IOJOB_DO_SWAP) + decrRefCount(job->val); + listDelNode(lists[i],ln); + zfree(job); + break; + case 1: /* io_processing */ + case 2: /* io_processed */ + job->canceled = 1; + break; + } + if (o->storage == REDIS_VM_LOADING) + o->storage = REDIS_VM_SWAPPED; + else if (o->storage == REDIS_VM_SWAPPING) + o->storage = REDIS_VM_MEMORY; + unlockThreadedIO(); + return; + } + } + } + unlockThreadedIO(); + assert(1 != 1); /* We should never reach this */ +} + +static void *IOThreadEntryPoint(void *arg) { + iojob *j; + listNode *ln; + REDIS_NOTUSED(arg); + + pthread_detach(pthread_self()); + while(1) { + /* Get a new job to process */ + lockThreadedIO(); + if (listLength(server.io_newjobs) == 0) { + /* No new jobs in queue, exit. */ + redisLog(REDIS_DEBUG,"Thread %lld exiting, nothing to do\n", + (long long) pthread_self()); + server.io_active_threads--; + unlockThreadedIO(); + return NULL; + } + ln = listFirst(server.io_newjobs); + j = ln->value; + listDelNode(server.io_newjobs,ln); + /* Add the job in the processing queue */ + j->thread = pthread_self(); + listAddNodeTail(server.io_processing,j); + ln = listLast(server.io_processing); /* We use ln later to remove it */ + unlockThreadedIO(); + redisLog(REDIS_DEBUG,"Thread %lld got a new job: %p about key '%s'\n", + (long long) pthread_self(), (void*)j, (char*)j->key->ptr); + + /* Process the Job */ + if (j->type == REDIS_IOJOB_LOAD) { + } else if (j->type == REDIS_IOJOB_PREPARE_SWAP) { + FILE *fp = fopen("/dev/null","w+"); + j->pages = rdbSavedObjectPages(j->val,fp); + fclose(fp); + } else if (j->type == REDIS_IOJOB_DO_SWAP) { + } + + /* Done: insert the job into the processed queue */ + redisLog(REDIS_DEBUG,"Thread %lld completed the job: %p\n", + (long long) pthread_self(), (void*)j); + lockThreadedIO(); + listDelNode(server.io_processing,ln); + listAddNodeTail(server.io_processed,j); + unlockThreadedIO(); + + /* Signal the main thread there is new stuff to process */ + assert(write(server.io_ready_pipe_write,"x",1) == 1); + } + return NULL; /* never reached */ +} + +static void spawnIOThread(void) { + pthread_t thread; + + pthread_create(&thread,NULL,IOThreadEntryPoint,NULL); + server.io_active_threads++; +} + +/* This function must be called while with threaded IO locked */ +static void queueIOJob(iojob *j) { + listAddNodeTail(server.io_newjobs,j); + if (server.io_active_threads < server.vm_max_threads) + spawnIOThread(); +} + +static int vmSwapObjectThreaded(robj *key, robj *val, redisDb *db) { + iojob *j; + + assert(key->storage == REDIS_VM_MEMORY); + assert(key->refcount == 1); + + j = zmalloc(sizeof(*j)); + j->type = REDIS_IOJOB_PREPARE_SWAP; + j->db = db; + j->key = dupStringObject(key); + j->val = val; + incrRefCount(val); + j->canceled = 0; + j->thread = (pthread_t) -1; + key->storage = REDIS_VM_SWAPPING; + + lockThreadedIO(); + queueIOJob(j); + unlockThreadedIO(); + return REDIS_OK; +} + /* ================================= Debugging ============================== */ static void debugCommand(redisClient *c) { @@ -7104,10 +7630,20 @@ static void debugCommand(redisClient *c) { } key = dictGetEntryKey(de); val = dictGetEntryVal(de); - addReplySds(c,sdscatprintf(sdsempty(), - "+Key at:%p refcount:%d, value at:%p refcount:%d encoding:%d serializedlength:%lld\r\n", + if (server.vm_enabled && (key->storage == REDIS_VM_MEMORY || + key->storage == REDIS_VM_SWAPPING)) { + addReplySds(c,sdscatprintf(sdsempty(), + "+Key at:%p refcount:%d, value at:%p refcount:%d " + "encoding:%d serializedlength:%lld\r\n", (void*)key, key->refcount, (void*)val, val->refcount, - val->encoding, rdbSavedObjectLen(val))); + val->encoding, rdbSavedObjectLen(val,NULL))); + } else { + addReplySds(c,sdscatprintf(sdsempty(), + "+Key at:%p refcount:%d, value swapped at: page %llu " + "using %llu pages\r\n", + (void*)key, key->refcount, (unsigned long long) key->vm.page, + (unsigned long long) key->vm.usedpages)); + } } else if (!strcasecmp(c->argv[1]->ptr,"swapout") && c->argc == 3) { dictEntry *de = dictFind(c->db->dict,c->argv[2]); robj *key, *val; @@ -7131,7 +7667,7 @@ static void debugCommand(redisClient *c) { /* Swap it */ if (key->storage != REDIS_VM_MEMORY) { addReplySds(c,sdsnew("-ERR This key is not in memory\r\n")); - } else if (vmSwapObject(key,val) == REDIS_OK) { + } else if (vmSwapObjectBlocking(key,val) == REDIS_OK) { dictGetEntryVal(de) = NULL; addReply(c,shared.ok); } else { @@ -7181,7 +7717,6 @@ static void daemonize(void) { FILE *fp; if (fork() != 0) exit(0); /* parent exits */ - printf("New pid: %d\n", getpid()); setsid(); /* create a new session */ /* Every output goes to /dev/null. If Redis is daemonized but @@ -7225,8 +7760,6 @@ int main(int argc, char **argv) { if (rdbLoad(server.dbfilename) == REDIS_OK) redisLog(REDIS_NOTICE,"DB loaded from disk"); } - if (aeCreateFileEvent(server.el, server.fd, AE_READABLE, - acceptHandler, NULL) == AE_ERR) oom("creating file event"); redisLog(REDIS_NOTICE,"The server is now ready to accept connections on port %d", server.port); aeMain(server.el); aeDeleteEventLoop(server.el);