pid_t bgsavechildpid;
pid_t bgrewritechildpid;
sds bgrewritebuf; /* buffer taken by parent during oppend only rewrite */
+ sds aofbuf; /* AOF buffer, written before entering the event loop */
struct saveparam *saveparams;
int saveparamslen;
char *logfile;
static robj *dupStringObject(robj *o);
static void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc);
static void replicationFeedMonitors(list *monitors, int dictid, robj **argv, int argc);
+static void flushAppendOnlyFile(void);
static void feedAppendOnlyFile(struct redisCommand *cmd, int dictid, robj **argv, int argc);
static int syncWithMaster(void);
static robj *tryObjectEncoding(robj *o);
static void beforeSleep(struct aeEventLoop *eventLoop) {
REDIS_NOTUSED(eventLoop);
+ /* Awake clients that got all the swapped keys they requested */
if (server.vm_enabled && listLength(server.io_ready_clients)) {
listIter li;
listNode *ln;
processInputBuffer(c);
}
}
+ /* Write the AOF buffer on disk */
+ flushAppendOnlyFile();
}
static void createSharedObjects(void) {
server.bgsavechildpid = -1;
server.bgrewritechildpid = -1;
server.bgrewritebuf = sdsempty();
+ server.aofbuf = sdsempty();
server.lastsave = time(NULL);
server.dirty = 0;
server.stat_numcommands = 0;
/* ============================== Append Only file ========================== */
+/* Write the append only file buffer on disk.
+ *
+ * Since we are required to write the AOF before replying to the client,
+ * and the only way the client socket can get a write is entering when the
+ * the event loop, we accumulate all the AOF writes in a memory
+ * buffer and write it on disk using this function just before entering
+ * the event loop again. */
+static void flushAppendOnlyFile(void) {
+ time_t now;
+ ssize_t nwritten;
+
+ if (sdslen(server.aofbuf) == 0) return;
+
+ /* We want to perform a single write. This should be guaranteed atomic
+ * at least if the filesystem we are writing is a real physical one.
+ * While this will save us against the server being killed I don't think
+ * there is much to do about the whole server stopping for power problems
+ * or alike */
+ nwritten = write(server.appendfd,server.aofbuf,sdslen(server.aofbuf));
+ if (nwritten != (signed)sdslen(server.aofbuf)) {
+ /* Ooops, we are in troubles. The best thing to do for now is
+ * aborting instead of giving the illusion that everything is
+ * working as expected. */
+ if (nwritten == -1) {
+ redisLog(REDIS_WARNING,"Exiting on error writing to the append-only file: %s",strerror(errno));
+ } else {
+ redisLog(REDIS_WARNING,"Exiting on short write while writing to the append-only file: %s",strerror(errno));
+ }
+ exit(1);
+ }
+ sdsfree(server.aofbuf);
+ server.aofbuf = sdsempty();
+
+ /* Fsync if needed */
+ now = time(NULL);
+ if (server.appendfsync == APPENDFSYNC_ALWAYS ||
+ (server.appendfsync == APPENDFSYNC_EVERYSEC &&
+ now-server.lastfsync > 1))
+ {
+ /* aof_fsync is defined as fdatasync() for Linux in order to avoid
+ * flushing metadata. */
+ aof_fsync(server.appendfd); /* Let's try to get this data on the disk */
+ server.lastfsync = now;
+ }
+}
+
static void feedAppendOnlyFile(struct redisCommand *cmd, int dictid, robj **argv, int argc) {
sds buf = sdsempty();
int j;
- ssize_t nwritten;
- time_t now;
robj *tmpargv[3];
/* The DB this command was targetting is not the same as the last command
decrRefCount(argv[j]);
}
- /* We want to perform a single write. This should be guaranteed atomic
- * at least if the filesystem we are writing is a real physical one.
- * While this will save us against the server being killed I don't think
- * there is much to do about the whole server stopping for power problems
- * or alike */
- nwritten = write(server.appendfd,buf,sdslen(buf));
- if (nwritten != (signed)sdslen(buf)) {
- /* Ooops, we are in troubles. The best thing to do for now is
- * to simply exit instead to give the illusion that everything is
- * working as expected. */
- if (nwritten == -1) {
- redisLog(REDIS_WARNING,"Exiting on error writing to the append-only file: %s",strerror(errno));
- } else {
- redisLog(REDIS_WARNING,"Exiting on short write while writing to the append-only file: %s",strerror(errno));
- }
- exit(1);
- }
+ /* Append to the AOF buffer. This will be flushed on disk just before
+ * of re-entering the event loop, so before the client will get a
+ * positive reply about the operation performed. */
+ server.aofbuf = sdscatlen(server.aofbuf,buf,sdslen(buf));
+
/* If a background append only file rewriting is in progress we want to
* accumulate the differences between the child DB and the current one
* in a buffer, so that when the child process will do its work we
server.bgrewritebuf = sdscatlen(server.bgrewritebuf,buf,sdslen(buf));
sdsfree(buf);
- now = time(NULL);
- if (server.appendfsync == APPENDFSYNC_ALWAYS ||
- (server.appendfsync == APPENDFSYNC_EVERYSEC &&
- now-server.lastfsync > 1))
- {
- /* aof_fsync is defined as fdatasync() for Linux in order to avoid
- * flushing metadata. */
- aof_fsync(server.appendfd); /* Let's try to get this data on the disk */
- server.lastfsync = now;
- }
}
/* In Redis commands are always executed in the context of a client, so in