X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/43222f253a60b8949d761bd3ef36cb061a3a4a3e..a950a84303038d3365442a48cc2c06f4b5d3f65e:/src/replication.c?ds=sidebyside diff --git a/src/replication.c b/src/replication.c index 87d575ca..e8297839 100644 --- a/src/replication.c +++ b/src/replication.c @@ -10,38 +10,8 @@ void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc) { listNode *ln; listIter li; - int outc = 0, j; - robj **outv; - /* We need 1+(ARGS*3) objects since commands are using the new protocol - * and we one 1 object for the first "*\r\n" multibulk count, then - * for every additional object we have "$\r\n" + object + "\r\n". */ - robj *static_outv[REDIS_STATIC_ARGS*3+1]; - robj *lenobj; - - if (argc <= REDIS_STATIC_ARGS) { - outv = static_outv; - } else { - outv = zmalloc(sizeof(robj*)*(argc*3+1)); - } - - lenobj = createObject(REDIS_STRING, - sdscatprintf(sdsempty(), "*%d\r\n", argc)); - lenobj->refcount = 0; - outv[outc++] = lenobj; - for (j = 0; j < argc; j++) { - lenobj = createObject(REDIS_STRING, - sdscatprintf(sdsempty(),"$%lu\r\n", - (unsigned long) stringObjectLen(argv[j]))); - lenobj->refcount = 0; - outv[outc++] = lenobj; - outv[outc++] = argv[j]; - outv[outc++] = shared.crlf; - } + int j; - /* Increment all the refcounts at start and decrement at end in order to - * be sure to free objects if there is no slave in a replication state - * able to be feed with commands */ - for (j = 0; j < outc; j++) incrRefCount(outv[j]); listRewind(slaves,&li); while((ln = listNext(&li))) { redisClient *slave = ln->value; @@ -49,7 +19,9 @@ void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc) { /* Don't feed slaves that are still waiting for BGSAVE to start */ if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_START) continue; - /* Feed all the other slaves, MONITORs and so on */ + /* Feed slaves that are waiting for the initial SYNC (so these commands + * are queued in the output buffer until the intial SYNC completes), + * or are already in sync with the master. */ if (slave->slaveseldb != dictid) { robj *selectcmd; @@ -73,10 +45,9 @@ void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc) { addReply(slave,selectcmd); slave->slaveseldb = dictid; } - for (j = 0; j < outc; j++) addReply(slave,outv[j]); + addReplyMultiBulkLen(slave,argc); + for (j = 0; j < argc; j++) addReplyBulk(slave,argv[j]); } - for (j = 0; j < outc; j++) decrRefCount(outv[j]); - if (outv != static_outv) zfree(outv); } void replicationFeedMonitors(list *monitors, int dictid, robj **argv, int argc) { @@ -118,7 +89,7 @@ void syncCommand(redisClient *c) { /* Refuse SYNC requests if we are a slave but the link with our master * is not ok... */ - if (server.masterhost && server.replstate != REDIS_REPL_CONNECTED) { + if (server.masterhost && server.repl_state != REDIS_REPL_CONNECTED) { addReplyError(c,"Can't SYNC while not connected with my master"); return; } @@ -135,7 +106,7 @@ void syncCommand(redisClient *c) { redisLog(REDIS_NOTICE,"Slave ask for synchronization"); /* Here we need to check if there is a background saving operation * in progress, or if it is required to start one */ - if (server.bgsavechildpid != -1) { + if (server.rdb_child_pid != -1) { /* Ok a background save is in progress. Let's check if it is a good * one for replication, i.e. if there is another slave that is * registering differences since the server forked to save */ @@ -151,8 +122,7 @@ void syncCommand(redisClient *c) { if (ln) { /* Perfect, the server is already registering differences for * another slave. Set the right state, and copy the buffer. */ - listRelease(c->reply); - c->reply = listDup(slave->reply); + copyClientOutputBuffer(c,slave); c->replstate = REDIS_REPL_WAIT_BGSAVE_END; redisLog(REDIS_NOTICE,"Waiting for end of BGSAVE for SYNC"); } else { @@ -164,7 +134,7 @@ void syncCommand(redisClient *c) { } else { /* Ok we don't have a BGSAVE in progress, let's start one */ redisLog(REDIS_NOTICE,"Starting BGSAVE for SYNC"); - if (rdbSaveBackground(server.dbfilename) != REDIS_OK) { + if (rdbSaveBackground(server.rdb_filename) != REDIS_OK) { redisLog(REDIS_NOTICE,"Replication failed, can't BGSAVE"); addReplyError(c,"Unable to perform background save"); return; @@ -258,7 +228,7 @@ void updateSlavesWaitingBgsave(int bgsaveerr) { redisLog(REDIS_WARNING,"SYNC failed. BGSAVE child returned an error"); continue; } - if ((slave->repldbfd = open(server.dbfilename,O_RDONLY)) == -1 || + if ((slave->repldbfd = open(server.rdb_filename,O_RDONLY)) == -1 || redis_fstat(slave->repldbfd,&buf) == -1) { freeClient(slave); redisLog(REDIS_WARNING,"SYNC failed. Can't open/stat DB after BGSAVE: %s", strerror(errno)); @@ -275,7 +245,7 @@ void updateSlavesWaitingBgsave(int bgsaveerr) { } } if (startbgsave) { - if (rdbSaveBackground(server.dbfilename) != REDIS_OK) { + if (rdbSaveBackground(server.rdb_filename) != REDIS_OK) { listIter li; listRewind(server.slaves,&li); @@ -294,14 +264,14 @@ void updateSlavesWaitingBgsave(int bgsaveerr) { /* Abort the async download of the bulk dataset while SYNC-ing with master */ void replicationAbortSyncTransfer(void) { - redisAssert(server.replstate == REDIS_REPL_TRANSFER); + redisAssert(server.repl_state == REDIS_REPL_TRANSFER); aeDeleteFileEvent(server.el,server.repl_transfer_s,AE_READABLE); close(server.repl_transfer_s); close(server.repl_transfer_fd); unlink(server.repl_transfer_tmpfile); zfree(server.repl_transfer_tmpfile); - server.replstate = REDIS_REPL_CONNECT; + server.repl_state = REDIS_REPL_CONNECT; } /* Asynchronously read the SYNC payload we receive from a master */ @@ -362,7 +332,7 @@ void readSyncBulkPayload(aeEventLoop *el, int fd, void *privdata, int mask) { server.repl_transfer_left -= nread; /* Check if the transfer is now complete */ if (server.repl_transfer_left == 0) { - if (rename(server.repl_transfer_tmpfile,server.dbfilename) == -1) { + if (rename(server.repl_transfer_tmpfile,server.rdb_filename) == -1) { redisLog(REDIS_WARNING,"Failed trying to rename the temp DB into dump.rdb in MASTER <-> SLAVE synchronization: %s", strerror(errno)); replicationAbortSyncTransfer(); return; @@ -374,7 +344,7 @@ void readSyncBulkPayload(aeEventLoop *el, int fd, void *privdata, int mask) { * rdbLoad() will call the event loop to process events from time to * time for non blocking loading. */ aeDeleteFileEvent(server.el,server.repl_transfer_s,AE_READABLE); - if (rdbLoad(server.dbfilename) != REDIS_OK) { + if (rdbLoad(server.rdb_filename) != REDIS_OK) { redisLog(REDIS_WARNING,"Failed trying to load the MASTER synchronization DB from disk"); replicationAbortSyncTransfer(); return; @@ -385,8 +355,24 @@ void readSyncBulkPayload(aeEventLoop *el, int fd, void *privdata, int mask) { server.master = createClient(server.repl_transfer_s); server.master->flags |= REDIS_MASTER; server.master->authenticated = 1; - server.replstate = REDIS_REPL_CONNECTED; + server.repl_state = REDIS_REPL_CONNECTED; redisLog(REDIS_NOTICE, "MASTER <-> SLAVE sync: Finished with success"); + /* Restart the AOF subsystem now that we finished the sync. This + * will trigger an AOF rewrite, and when done will start appending + * to the new file. */ + if (server.aof_state != REDIS_AOF_OFF) { + int retry = 10; + + stopAppendOnly(); + while (retry-- && startAppendOnly() == REDIS_ERR) { + redisLog(REDIS_WARNING,"Failed enabling the AOF after successful master synchrnization! Trying it again in one second."); + sleep(1); + } + if (!retry) { + redisLog(REDIS_WARNING,"FATAL: this slave instance finished the synchronization with its master, but the AOF can't be turned on. Exiting now."); + exit(1); + } + } } return; @@ -403,10 +389,18 @@ void syncWithMaster(aeEventLoop *el, int fd, void *privdata, int mask) { REDIS_NOTUSED(privdata); REDIS_NOTUSED(mask); + /* If this event fired after the user turned the instance into a master + * with SLAVEOF NO ONE we must just return ASAP. */ + if (server.repl_state == REDIS_REPL_NONE) { + close(fd); + return; + } + + redisLog(REDIS_NOTICE,"Non blocking connect for SYNC fired the event."); /* This event should only be triggered once since it is used to have a * non-blocking connect(2) to the master. It has been triggered when this * function is called, so we can delete it. */ - aeDeleteFileEvent(server.el,fd,AE_WRITABLE); + aeDeleteFileEvent(server.el,fd,AE_READABLE|AE_WRITABLE); /* AUTH with the master if required. */ if(server.masterauth) { @@ -459,7 +453,7 @@ void syncWithMaster(aeEventLoop *el, int fd, void *privdata, int mask) { goto error; } - server.replstate = REDIS_REPL_TRANSFER; + server.repl_state = REDIS_REPL_TRANSFER; server.repl_transfer_left = -1; server.repl_transfer_fd = dfd; server.repl_transfer_lastio = time(NULL); @@ -467,7 +461,7 @@ void syncWithMaster(aeEventLoop *el, int fd, void *privdata, int mask) { return; error: - server.replstate = REDIS_REPL_CONNECT; + server.repl_state = REDIS_REPL_CONNECT; close(fd); return; } @@ -482,7 +476,7 @@ int connectWithMaster(void) { return REDIS_ERR; } - if (aeCreateFileEvent(server.el,fd,AE_WRITABLE,syncWithMaster,NULL) == + if (aeCreateFileEvent(server.el,fd,AE_READABLE|AE_WRITABLE,syncWithMaster,NULL) == AE_ERR) { close(fd); @@ -490,11 +484,24 @@ int connectWithMaster(void) { return REDIS_ERR; } + server.repl_transfer_lastio = time(NULL); server.repl_transfer_s = fd; - server.replstate = REDIS_REPL_CONNECTING; + server.repl_state = REDIS_REPL_CONNECTING; return REDIS_OK; } +/* This function can be called when a non blocking connection is currently + * in progress to undo it. */ +void undoConnectWithMaster(void) { + int fd = server.repl_transfer_s; + + redisAssert(server.repl_state == REDIS_REPL_CONNECTING); + aeDeleteFileEvent(server.el,fd,AE_READABLE|AE_WRITABLE); + close(fd); + server.repl_transfer_s = -1; + server.repl_state = REDIS_REPL_CONNECT; +} + void slaveofCommand(redisClient *c) { if (!strcasecmp(c->argv[1]->ptr,"no") && !strcasecmp(c->argv[2]->ptr,"one")) { @@ -502,19 +509,35 @@ void slaveofCommand(redisClient *c) { sdsfree(server.masterhost); server.masterhost = NULL; if (server.master) freeClient(server.master); - if (server.replstate == REDIS_REPL_TRANSFER) + if (server.repl_state == REDIS_REPL_TRANSFER) replicationAbortSyncTransfer(); - server.replstate = REDIS_REPL_NONE; + else if (server.repl_state == REDIS_REPL_CONNECTING) + undoConnectWithMaster(); + server.repl_state = REDIS_REPL_NONE; redisLog(REDIS_NOTICE,"MASTER MODE enabled (user request)"); } } else { + long port; + + if ((getLongFromObjectOrReply(c, c->argv[2], &port, NULL) != REDIS_OK)) + return; + + /* Check if we are already attached to the specified slave */ + if (server.masterhost && !strcasecmp(server.masterhost,c->argv[1]->ptr) + && server.masterport == port) { + redisLog(REDIS_NOTICE,"SLAVE OF would result into synchronization with the master we are already connected with. No operation performed."); + addReplySds(c,sdsnew("+OK Already connected to specified master\r\n")); + return; + } + /* There was no previous master or the user specified a different one, + * we can continue. */ sdsfree(server.masterhost); server.masterhost = sdsdup(c->argv[1]->ptr); - server.masterport = atoi(c->argv[2]->ptr); + server.masterport = port; if (server.master) freeClient(server.master); - if (server.replstate == REDIS_REPL_TRANSFER) + if (server.repl_state == REDIS_REPL_TRANSFER) replicationAbortSyncTransfer(); - server.replstate = REDIS_REPL_CONNECT; + server.repl_state = REDIS_REPL_CONNECT; redisLog(REDIS_NOTICE,"SLAVE OF %s:%d enabled (user request)", server.masterhost, server.masterport); } @@ -523,32 +546,36 @@ void slaveofCommand(redisClient *c) { /* --------------------------- REPLICATION CRON ---------------------------- */ -#define REDIS_REPL_TIMEOUT 60 -#define REDIS_REPL_PING_SLAVE_PERIOD 10 - void replicationCron(void) { + /* Non blocking connection timeout? */ + if (server.masterhost && server.repl_state == REDIS_REPL_CONNECTING && + (time(NULL)-server.repl_transfer_lastio) > server.repl_timeout) + { + redisLog(REDIS_WARNING,"Timeout connecting to the MASTER..."); + undoConnectWithMaster(); + } + /* Bulk transfer I/O timeout? */ - if (server.masterhost && server.replstate == REDIS_REPL_TRANSFER && - (time(NULL)-server.repl_transfer_lastio) > REDIS_REPL_TIMEOUT) + if (server.masterhost && server.repl_state == REDIS_REPL_TRANSFER && + (time(NULL)-server.repl_transfer_lastio) > server.repl_timeout) { redisLog(REDIS_WARNING,"Timeout receiving bulk data from MASTER..."); replicationAbortSyncTransfer(); } /* Timed out master when we are an already connected slave? */ - if (server.masterhost && server.replstate == REDIS_REPL_CONNECTED && - (time(NULL)-server.master->lastinteraction) > REDIS_REPL_TIMEOUT) + if (server.masterhost && server.repl_state == REDIS_REPL_CONNECTED && + (time(NULL)-server.master->lastinteraction) > server.repl_timeout) { redisLog(REDIS_WARNING,"MASTER time out: no data nor PING received..."); freeClient(server.master); } /* Check if we should connect to a MASTER */ - if (server.replstate == REDIS_REPL_CONNECT) { + if (server.repl_state == REDIS_REPL_CONNECT) { redisLog(REDIS_NOTICE,"Connecting to MASTER..."); if (connectWithMaster() == REDIS_OK) { redisLog(REDIS_NOTICE,"MASTER <-> SLAVE sync started"); - if (server.appendonly) rewriteAppendOnlyFileBackground(); } } @@ -556,7 +583,7 @@ void replicationCron(void) { * So slaves can implement an explicit timeout to masters, and will * be able to detect a link disconnection even if the TCP connection * will not actually go down. */ - if (!(server.cronloops % (REDIS_REPL_PING_SLAVE_PERIOD*10))) { + if (!(server.cronloops % (server.repl_ping_slave_period*10))) { listIter li; listNode *ln; @@ -569,7 +596,7 @@ void replicationCron(void) { if (slave->replstate == REDIS_REPL_SEND_BULK) continue; if (slave->replstate == REDIS_REPL_ONLINE) { /* If the slave is online send a normal ping */ - addReplySds(slave,sdsnew("PING\r\n")); + addReplySds(slave,sdsnew("*1\r\n$4\r\nPING\r\n")); } else { /* Otherwise we are in the pre-synchronization stage. * Just a newline will do the work of refreshing the