X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/a11c87477754322863a51c22cb6a7614ba8ebaf0..ecd82f59fe5296de2733154bfcf1a4b95d4547aa:/src/replication.c?ds=sidebyside diff --git a/src/replication.c b/src/replication.c index dd42fcf1..c1e46191 100644 --- a/src/replication.c +++ b/src/replication.c @@ -3,6 +3,7 @@ #include <sys/time.h> #include <unistd.h> #include <fcntl.h> +#include <sys/socket.h> #include <sys/stat.h> /* ---------------------------------- MASTER -------------------------------- */ @@ -25,24 +26,15 @@ void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc) { if (slave->slaveseldb != dictid) { robj *selectcmd; - switch(dictid) { - case 0: selectcmd = shared.select0; break; - case 1: selectcmd = shared.select1; break; - case 2: selectcmd = shared.select2; break; - case 3: selectcmd = shared.select3; break; - case 4: selectcmd = shared.select4; break; - case 5: selectcmd = shared.select5; break; - case 6: selectcmd = shared.select6; break; - case 7: selectcmd = shared.select7; break; - case 8: selectcmd = shared.select8; break; - case 9: selectcmd = shared.select9; break; - default: + if (dictid >= 0 && dictid < REDIS_SHARED_SELECT_CMDS) { + selectcmd = shared.select[dictid]; + incrRefCount(selectcmd); + } else { selectcmd = createObject(REDIS_STRING, sdscatprintf(sdsempty(),"select %d\r\n",dictid)); - selectcmd->refcount = 0; - break; } addReply(slave,selectcmd); + decrRefCount(selectcmd); slave->slaveseldb = dictid; } addReplyMultiBulkLen(slave,argc); @@ -50,17 +42,23 @@ void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc) { } } -void replicationFeedMonitors(list *monitors, int dictid, robj **argv, int argc) { +void replicationFeedMonitors(redisClient *c, list *monitors, int dictid, robj **argv, int argc) { listNode *ln; listIter li; - int j; + int j, port; sds cmdrepr = sdsnew("+"); robj *cmdobj; + char ip[32]; struct timeval tv; gettimeofday(&tv,NULL); cmdrepr = sdscatprintf(cmdrepr,"%ld.%06ld ",(long)tv.tv_sec,(long)tv.tv_usec); - if (dictid != 0) cmdrepr = sdscatprintf(cmdrepr,"(db %d) ", dictid); + if (c->flags & REDIS_LUA_CLIENT) { + cmdrepr = sdscatprintf(cmdrepr,"[%d lua] ", dictid); + } else { + anetPeerToString(c->fd,ip,&port); + cmdrepr = sdscatprintf(cmdrepr,"[%d %s:%d] ", dictid,ip,port); + } for (j = 0; j < argc; j++) { if (argv[j]->encoding == REDIS_ENCODING_INT) { @@ -148,6 +146,46 @@ void syncCommand(redisClient *c) { return; } +/* REPLCONF <option> <value> <option> <value> ... + * This command is used by a slave in order to configure the replication + * process before starting it with the SYNC command. + * + * Currently the only use of this command is to communicate to the master + * what is the listening port of the Slave redis instance, so that the + * master can accurately list slaves and their listening ports in + * the INFO output. + * + * In the future the same command can be used in order to configure + * the replication to initiate an incremental replication instead of a + * full resync. */ +void replconfCommand(redisClient *c) { + int j; + + if ((c->argc % 2) == 0) { + /* Number of arguments must be odd to make sure that every + * option has a corresponding value. */ + addReply(c,shared.syntaxerr); + return; + } + + /* Process every option-value pair. */ + for (j = 1; j < c->argc; j+=2) { + if (!strcasecmp(c->argv[j]->ptr,"listening-port")) { + long port; + + if ((getLongFromObjectOrReply(c,c->argv[j+1], + &port,NULL) != REDIS_OK)) + return; + c->slave_listening_port = port; + } else { + addReplyErrorFormat(c,"Unrecognized REPLCONF option: %s", + (char*)c->argv[j]->ptr); + return; + } + } + addReply(c,shared.ok); +} + void sendBulkToSlave(aeEventLoop *el, int fd, void *privdata, int mask) { redisClient *slave = privdata; REDIS_NOTUSED(el); @@ -197,7 +235,6 @@ void sendBulkToSlave(aeEventLoop *el, int fd, void *privdata, int mask) { freeClient(slave); return; } - addReplySds(slave,sdsempty()); redisLog(REDIS_NOTICE,"Synchronization with slave succeeded"); } } @@ -275,17 +312,19 @@ void replicationAbortSyncTransfer(void) { } /* Asynchronously read the SYNC payload we receive from a master */ +#define REPL_MAX_WRITTEN_BEFORE_FSYNC (1024*1024*8) /* 8 MB */ void readSyncBulkPayload(aeEventLoop *el, int fd, void *privdata, int mask) { char buf[4096]; ssize_t nread, readlen; + off_t left; REDIS_NOTUSED(el); REDIS_NOTUSED(privdata); REDIS_NOTUSED(mask); - /* If repl_transfer_left == -1 we still have to read the bulk length + /* If repl_transfer_size == -1 we still have to read the bulk length * from the master reply. */ - if (server.repl_transfer_left == -1) { - if (syncReadLine(fd,buf,1024,server.repl_syncio_timeout) == -1) { + if (server.repl_transfer_size == -1) { + if (syncReadLine(fd,buf,1024,server.repl_syncio_timeout*1000) == -1) { redisLog(REDIS_WARNING, "I/O error reading bulk count from MASTER: %s", strerror(errno)); @@ -301,22 +340,22 @@ void readSyncBulkPayload(aeEventLoop *el, int fd, void *privdata, int mask) { /* At this stage just a newline works as a PING in order to take * the connection live. So we refresh our last interaction * timestamp. */ - server.repl_transfer_lastio = time(NULL); + server.repl_transfer_lastio = server.unixtime; return; } else if (buf[0] != '$') { redisLog(REDIS_WARNING,"Bad protocol from MASTER, the first byte is not '$', are you sure the host and port are right?"); goto error; } - server.repl_transfer_left = strtol(buf+1,NULL,10); + server.repl_transfer_size = strtol(buf+1,NULL,10); redisLog(REDIS_NOTICE, "MASTER <-> SLAVE sync: receiving %ld bytes from master", - server.repl_transfer_left); + server.repl_transfer_size); return; } /* Read bulk data */ - readlen = (server.repl_transfer_left < (signed)sizeof(buf)) ? - server.repl_transfer_left : (signed)sizeof(buf); + left = server.repl_transfer_size - server.repl_transfer_read; + readlen = (left < (signed)sizeof(buf)) ? left : (signed)sizeof(buf); nread = read(fd,buf,readlen); if (nread <= 0) { redisLog(REDIS_WARNING,"I/O error trying to sync with MASTER: %s", @@ -324,14 +363,28 @@ void readSyncBulkPayload(aeEventLoop *el, int fd, void *privdata, int mask) { replicationAbortSyncTransfer(); return; } - server.repl_transfer_lastio = time(NULL); + server.repl_transfer_lastio = server.unixtime; if (write(server.repl_transfer_fd,buf,nread) != nread) { - redisLog(REDIS_WARNING,"Write error or short write writing to the DB dump file needed for MASTER <-> SLAVE synchrnonization: %s", strerror(errno)); + redisLog(REDIS_WARNING,"Write error or short write writing to the DB dump file needed for MASTER <-> SLAVE synchronization: %s", strerror(errno)); goto error; } - server.repl_transfer_left -= nread; + server.repl_transfer_read += nread; + + /* Sync data on disk from time to time, otherwise at the end of the transfer + * we may suffer a big delay as the memory buffers are copied into the + * actual disk. */ + if (server.repl_transfer_read >= + server.repl_transfer_last_fsync_off + REPL_MAX_WRITTEN_BEFORE_FSYNC) + { + off_t sync_size = server.repl_transfer_read - + server.repl_transfer_last_fsync_off; + rdb_fsync_range(server.repl_transfer_fd, + server.repl_transfer_last_fsync_off, sync_size); + server.repl_transfer_last_fsync_off += sync_size; + } + /* Check if the transfer is now complete */ - if (server.repl_transfer_left == 0) { + if (server.repl_transfer_read == server.repl_transfer_size) { 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(); @@ -382,9 +435,57 @@ error: return; } +/* Send a synchronous command to the master. Used to send AUTH and + * REPLCONF commands before starting the replication with SYNC. + * + * On success NULL is returned. + * On error an sds string describing the error is returned. + */ +char *sendSynchronousCommand(int fd, ...) { + va_list ap; + sds cmd = sdsempty(); + char *arg, buf[256]; + + /* Create the command to send to the master, we use simple inline + * protocol for simplicity as currently we only send simple strings. */ + va_start(ap,fd); + while(1) { + arg = va_arg(ap, char*); + if (arg == NULL) break; + + if (sdslen(cmd) != 0) cmd = sdscatlen(cmd," ",1); + cmd = sdscat(cmd,arg); + } + cmd = sdscatlen(cmd,"\r\n",2); + + /* Transfer command to the server. */ + if (syncWrite(fd,cmd,sdslen(cmd),server.repl_syncio_timeout*1000) == -1) { + sdsfree(cmd); + return sdscatprintf(sdsempty(),"Writing to master: %s", + strerror(errno)); + } + sdsfree(cmd); + + /* Read the reply from the server. */ + if (syncReadLine(fd,buf,sizeof(buf),server.repl_syncio_timeout*1000) == -1) + { + return sdscatprintf(sdsempty(),"Reading from master: %s", + strerror(errno)); + } + + /* Check for errors from the server. */ + if (buf[0] != '+') { + return sdscatprintf(sdsempty(),"Error from master: %s", buf); + } + + return NULL; /* No errors. */ +} + void syncWithMaster(aeEventLoop *el, int fd, void *privdata, int mask) { - char buf[1024], tmpfile[256]; + char tmpfile[256], *err; int dfd, maxtries = 5; + int sockerr = 0; + socklen_t errlen = sizeof(sockerr); REDIS_NOTUSED(el); REDIS_NOTUSED(privdata); REDIS_NOTUSED(mask); @@ -396,37 +497,90 @@ void syncWithMaster(aeEventLoop *el, int fd, void *privdata, int mask) { 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_READABLE|AE_WRITABLE); + /* Check for errors in the socket. */ + if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &sockerr, &errlen) == -1) + sockerr = errno; + if (sockerr) { + aeDeleteFileEvent(server.el,fd,AE_READABLE|AE_WRITABLE); + redisLog(REDIS_WARNING,"Error condition on socket for SYNC: %s", + strerror(sockerr)); + goto error; + } - /* AUTH with the master if required. */ - if(server.masterauth) { - char authcmd[1024]; - size_t authlen; + /* If we were connecting, it's time to send a non blocking PING, we want to + * make sure the master is able to reply before going into the actual + * replication process where we have long timeouts in the order of + * seconds (in the meantime the slave would block). */ + if (server.repl_state == REDIS_REPL_CONNECTING) { + redisLog(REDIS_NOTICE,"Non blocking connect for SYNC fired the event."); + /* Delete the writable event so that the readable event remains + * registered and we can wait for the PONG reply. */ + aeDeleteFileEvent(server.el,fd,AE_WRITABLE); + server.repl_state = REDIS_REPL_RECEIVE_PONG; + /* Send the PING, don't check for errors at all, we have the timeout + * that will take care about this. */ + syncWrite(fd,"PING\r\n",6,100); + return; + } + + /* Receive the PONG command. */ + if (server.repl_state == REDIS_REPL_RECEIVE_PONG) { + char buf[1024]; - authlen = snprintf(authcmd,sizeof(authcmd),"AUTH %s\r\n",server.masterauth); - if (syncWrite(fd,authcmd,authlen,server.repl_syncio_timeout) == -1) { - redisLog(REDIS_WARNING,"Unable to AUTH to MASTER: %s", + /* Delete the readable event, we no longer need it now that there is + * the PING reply to read. */ + aeDeleteFileEvent(server.el,fd,AE_READABLE); + + /* Read the reply with explicit timeout. */ + buf[0] = '\0'; + if (syncReadLine(fd,buf,sizeof(buf), + server.repl_syncio_timeout*1000) == -1) + { + redisLog(REDIS_WARNING, + "I/O error reading PING reply from master: %s", strerror(errno)); goto error; } - /* Read the AUTH result. */ - if (syncReadLine(fd,buf,1024,server.repl_syncio_timeout) == -1) { - redisLog(REDIS_WARNING,"I/O error reading auth result from MASTER: %s", - strerror(errno)); + + /* We don't care about the reply, it can be +PONG or an error since + * the server requires AUTH. As long as it replies correctly, it's + * fine from our point of view. */ + if (buf[0] != '-' && buf[0] != '+') { + redisLog(REDIS_WARNING,"Unexpected reply to PING from master."); goto error; + } else { + redisLog(REDIS_NOTICE, + "Master replied to PING, replication can continue..."); } - if (buf[0] != '+') { - redisLog(REDIS_WARNING,"Cannot AUTH to MASTER, is the masterauth password correct?"); + } + + /* AUTH with the master if required. */ + if(server.masterauth) { + err = sendSynchronousCommand(fd,"AUTH",server.masterauth,NULL); + if (err) { + redisLog(REDIS_WARNING,"Unable to AUTH to MASTER: %s",err); + sdsfree(err); goto error; } } + /* Set the slave port, so that Master's INFO command can list the + * slave listening port correctly. */ + { + sds port = sdsfromlonglong(server.port); + err = sendSynchronousCommand(fd,"REPLCONF","listening-port",port, + NULL); + sdsfree(port); + /* Ignore the error if any, not all the Redis versions support + * REPLCONF listening-port. */ + if (err) { + redisLog(REDIS_NOTICE,"(non critical): Master does not understand REPLCONF listening-port: %s", err); + sdsfree(err); + } + } + /* Issue the SYNC command */ - if (syncWrite(fd,"SYNC \r\n",7,server.repl_syncio_timeout) == -1) { + if (syncWrite(fd,"SYNC\r\n",6,server.repl_syncio_timeout*1000) == -1) { redisLog(REDIS_WARNING,"I/O error writing to MASTER: %s", strerror(errno)); goto error; @@ -435,7 +589,7 @@ void syncWithMaster(aeEventLoop *el, int fd, void *privdata, int mask) { /* Prepare a suitable temp file for bulk transfer */ while(maxtries--) { snprintf(tmpfile,256, - "temp-%d.%ld.rdb",(int)time(NULL),(long int)getpid()); + "temp-%d.%ld.rdb",(int)server.unixtime,(long int)getpid()); dfd = open(tmpfile,O_CREAT|O_WRONLY|O_EXCL,0644); if (dfd != -1) break; sleep(1); @@ -454,15 +608,18 @@ void syncWithMaster(aeEventLoop *el, int fd, void *privdata, int mask) { } server.repl_state = REDIS_REPL_TRANSFER; - server.repl_transfer_left = -1; + server.repl_transfer_size = -1; + server.repl_transfer_read = 0; + server.repl_transfer_last_fsync_off = 0; server.repl_transfer_fd = dfd; - server.repl_transfer_lastio = time(NULL); + server.repl_transfer_lastio = server.unixtime; server.repl_transfer_tmpfile = zstrdup(tmpfile); return; error: - server.repl_state = REDIS_REPL_CONNECT; close(fd); + server.repl_transfer_s = -1; + server.repl_state = REDIS_REPL_CONNECT; return; } @@ -484,7 +641,7 @@ int connectWithMaster(void) { return REDIS_ERR; } - server.repl_transfer_lastio = time(NULL); + server.repl_transfer_lastio = server.unixtime; server.repl_transfer_s = fd; server.repl_state = REDIS_REPL_CONNECTING; return REDIS_OK; @@ -495,7 +652,8 @@ int connectWithMaster(void) { void undoConnectWithMaster(void) { int fd = server.repl_transfer_s; - redisAssert(server.repl_state == REDIS_REPL_CONNECTING); + redisAssert(server.repl_state == REDIS_REPL_CONNECTING || + server.repl_state == REDIS_REPL_RECEIVE_PONG); aeDeleteFileEvent(server.el,fd,AE_READABLE|AE_WRITABLE); close(fd); server.repl_transfer_s = -1; @@ -511,7 +669,8 @@ void slaveofCommand(redisClient *c) { if (server.master) freeClient(server.master); if (server.repl_state == REDIS_REPL_TRANSFER) replicationAbortSyncTransfer(); - else if (server.repl_state == REDIS_REPL_CONNECTING) + else if (server.repl_state == REDIS_REPL_CONNECTING || + server.repl_state == REDIS_REPL_RECEIVE_PONG) undoConnectWithMaster(); server.repl_state = REDIS_REPL_NONE; redisLog(REDIS_NOTICE,"MASTER MODE enabled (user request)"); @@ -535,6 +694,7 @@ void slaveofCommand(redisClient *c) { server.masterhost = sdsdup(c->argv[1]->ptr); server.masterport = port; if (server.master) freeClient(server.master); + disconnectSlaves(); /* Force our slaves to resync with us as well. */ if (server.repl_state == REDIS_REPL_TRANSFER) replicationAbortSyncTransfer(); server.repl_state = REDIS_REPL_CONNECT; @@ -548,7 +708,9 @@ void slaveofCommand(redisClient *c) { void replicationCron(void) { /* Non blocking connection timeout? */ - if (server.masterhost && server.repl_state == REDIS_REPL_CONNECTING && + if (server.masterhost && + (server.repl_state == REDIS_REPL_CONNECTING || + server.repl_state == REDIS_REPL_RECEIVE_PONG) && (time(NULL)-server.repl_transfer_lastio) > server.repl_timeout) { redisLog(REDIS_WARNING,"Timeout connecting to the MASTER..."); @@ -559,7 +721,7 @@ void replicationCron(void) { 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..."); + redisLog(REDIS_WARNING,"Timeout receiving bulk data from MASTER... If the problem persists try to set the 'repl-timeout' parameter in redis.conf to a larger value."); replicationAbortSyncTransfer(); } @@ -583,7 +745,7 @@ 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 % (server.repl_ping_slave_period*10))) { + if (!(server.cronloops % (server.repl_ping_slave_period * REDIS_HZ))) { listIter li; listNode *ln; @@ -596,7 +758,7 @@ 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