diff --git a/redis.c b/redis.c index f96744f1..651d4d45 100644 --- a/redis.c +++ b/redis.c @@ -561,6 +561,7 @@ static void freeIOJob(iojob *j); static void queueIOJob(iojob *j); static int vmWriteObjectOnSwap(robj *o, off_t page); static robj *vmReadObjectFromSwap(off_t page, int type); +static void waitZeroActiveThreads(void); static void authCommand(redisClient *c); static void pingCommand(redisClient *c); @@ -3085,6 +3086,7 @@ static int rdbSaveBackground(char *filename) { pid_t childpid; if (server.bgsavechildpid != -1) return REDIS_ERR; + if (server.vm_enabled) waitZeroActiveThreads(); if ((childpid = fork()) == 0) { /* Child */ close(server.fd); @@ -6906,6 +6908,7 @@ static int rewriteAppendOnlyFileBackground(void) { pid_t childpid; if (server.bgrewritechildpid != -1) return REDIS_ERR; + if (server.vm_enabled) waitZeroActiveThreads(); if ((childpid = fork()) == 0) { /* Child */ char tmpfile[256]; @@ -7669,6 +7672,20 @@ static void spawnIOThread(void) { server.io_active_threads++; } +/* We need to wait for the last thread to exit before we are able to + * fork() in order to BGSAVE or BGREWRITEAOF. */ +static void waitZeroActiveThreads(void) { + while(1) { + lockThreadedIO(); + if (server.io_active_threads == 0) { + unlockThreadedIO(); + return; + } + unlockThreadedIO(); + usleep(10000); /* 10 milliseconds */ + } +} + /* This function must be called while with threaded IO locked */ static void queueIOJob(iojob *j) { redisLog(REDIS_DEBUG,"Queued IO Job %p type %d about key '%s'\n",