X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/dbd8c753c43b83fd326acc7974768261589b239e..ec0f483de2ffe41ecb26a485d6b424c3126438fe:/src/replication.c diff --git a/src/replication.c b/src/replication.c index cc1ac980..c1e46191 100644 --- a/src/replication.c +++ b/src/replication.c @@ -3,6 +3,7 @@ #include #include #include +#include #include /* ---------------------------------- MASTER -------------------------------- */ @@ -311,16 +312,18 @@ 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 (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", @@ -343,16 +346,16 @@ void readSyncBulkPayload(aeEventLoop *el, int fd, void *privdata, int mask) { 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", @@ -365,9 +368,23 @@ void readSyncBulkPayload(aeEventLoop *el, int fd, void *privdata, int mask) { 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(); @@ -419,7 +436,7 @@ error: } /* Send a synchronous command to the master. Used to send AUTH and - * REPLCONF commadns before starting the replication with SYNC. + * REPLCONF commands before starting the replication with SYNC. * * On success NULL is returned. * On error an sds string describing the error is returned. @@ -467,6 +484,8 @@ char *sendSynchronousCommand(int fd, ...) { void syncWithMaster(aeEventLoop *el, int fd, void *privdata, int mask) { 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); @@ -478,11 +497,62 @@ 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; + } + + /* 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]; + + /* 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; + } + + /* 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..."); + } + } /* AUTH with the master if required. */ if(server.masterauth) { @@ -538,15 +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 = 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; } @@ -579,7 +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; @@ -595,7 +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)"); @@ -633,7 +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..."); @@ -644,7 +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(); } @@ -668,7 +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;