diff options
Diffstat (limited to 'src/backend/postmaster/checkpointer.c')
| -rw-r--r-- | src/backend/postmaster/checkpointer.c | 73 |
1 files changed, 38 insertions, 35 deletions
diff --git a/src/backend/postmaster/checkpointer.c b/src/backend/postmaster/checkpointer.c index 6aeade92e6..87aa4e1ba0 100644 --- a/src/backend/postmaster/checkpointer.c +++ b/src/backend/postmaster/checkpointer.c @@ -2,7 +2,7 @@ * * checkpointer.c * - * The checkpointer is new as of Postgres 9.2. It handles all checkpoints. + * The checkpointer is new as of Postgres 9.2. It handles all checkpoints. * Checkpoints are automatically dispatched after a certain amount of time has * elapsed since the last one, and it can be signaled to perform requested * checkpoints as well. (The GUC parameter that mandates a checkpoint every @@ -14,7 +14,7 @@ * subprocess finishes, or as soon as recovery begins if we are doing archive * recovery. It remains alive until the postmaster commands it to terminate. * Normal termination is by SIGUSR2, which instructs the checkpointer to - * execute a shutdown checkpoint and then exit(0). (All backends must be + * execute a shutdown checkpoint and then exit(0). (All backends must be * stopped before SIGUSR2 is issued!) Emergency termination is by SIGQUIT; * like any backend, the checkpointer will simply abort and exit on SIGQUIT. * @@ -113,7 +113,7 @@ typedef struct typedef struct { - pid_t checkpointer_pid; /* PID (0 if not started) */ + pid_t checkpointer_pid; /* PID (0 if not started) */ slock_t ckpt_lck; /* protects all the ckpt_* fields */ @@ -199,7 +199,7 @@ CheckpointerMain(void) /* * If possible, make this process a group leader, so that the postmaster - * can signal any child processes too. (checkpointer probably never has + * can signal any child processes too. (checkpointer probably never has * any child processes, but for consistency we make all postmaster child * processes do this.) */ @@ -216,10 +216,11 @@ CheckpointerMain(void) * want to wait for the backends to exit, whereupon the postmaster will * tell us it's okay to shut down (via SIGUSR2). */ - pqsignal(SIGHUP, ChkptSigHupHandler); /* set flag to read config file */ - pqsignal(SIGINT, ReqCheckpointHandler); /* request checkpoint */ - pqsignal(SIGTERM, SIG_IGN); /* ignore SIGTERM */ - pqsignal(SIGQUIT, chkpt_quickdie); /* hard crash time */ + pqsignal(SIGHUP, ChkptSigHupHandler); /* set flag to read config + * file */ + pqsignal(SIGINT, ReqCheckpointHandler); /* request checkpoint */ + pqsignal(SIGTERM, SIG_IGN); /* ignore SIGTERM */ + pqsignal(SIGQUIT, chkpt_quickdie); /* hard crash time */ pqsignal(SIGALRM, SIG_IGN); pqsignal(SIGPIPE, SIG_IGN); pqsignal(SIGUSR1, chkpt_sigusr1_handler); @@ -255,10 +256,10 @@ CheckpointerMain(void) * TopMemoryContext, but resetting that would be a really bad idea. */ checkpointer_context = AllocSetContextCreate(TopMemoryContext, - "Checkpointer", - ALLOCSET_DEFAULT_MINSIZE, - ALLOCSET_DEFAULT_INITSIZE, - ALLOCSET_DEFAULT_MAXSIZE); + "Checkpointer", + ALLOCSET_DEFAULT_MINSIZE, + ALLOCSET_DEFAULT_INITSIZE, + ALLOCSET_DEFAULT_MAXSIZE); MemoryContextSwitchTo(checkpointer_context); /* @@ -280,7 +281,8 @@ CheckpointerMain(void) /* * These operations are really just a minimal subset of * AbortTransaction(). We don't have very many resources to worry - * about in checkpointer, but we do have LWLocks, buffers, and temp files. + * about in checkpointer, but we do have LWLocks, buffers, and temp + * files. */ LWLockReleaseAll(); AbortBufferIO(); @@ -351,9 +353,8 @@ CheckpointerMain(void) ThisTimeLineID = GetRecoveryTargetTLI(); /* - * Ensure all shared memory values are set correctly for the config. - * Doing this here ensures no race conditions from other concurrent - * updaters. + * Ensure all shared memory values are set correctly for the config. Doing + * this here ensures no race conditions from other concurrent updaters. */ UpdateSharedMemoryConfig(); @@ -389,9 +390,9 @@ CheckpointerMain(void) ProcessConfigFile(PGC_SIGHUP); /* - * Checkpointer is the last process to shut down, so we ask - * it to hold the keys for a range of other tasks required - * most of which have nothing to do with checkpointing at all. + * Checkpointer is the last process to shut down, so we ask it to + * hold the keys for a range of other tasks required most of which + * have nothing to do with checkpointing at all. * * For various reasons, some config values can change dynamically * so the primary copy of them is held in shared memory to make @@ -490,7 +491,8 @@ CheckpointerMain(void) errhint("Consider increasing the configuration parameter \"checkpoint_segments\"."))); /* - * Initialize checkpointer-private variables used during checkpoint + * Initialize checkpointer-private variables used during + * checkpoint */ ckpt_active = true; if (!do_restartpoint) @@ -558,8 +560,8 @@ CheckpointerMain(void) pgstat_send_bgwriter(); /* - * Sleep until we are signaled or it's time for another checkpoint - * or xlog file switch. + * Sleep until we are signaled or it's time for another checkpoint or + * xlog file switch. */ now = (pg_time_t) time(NULL); elapsed_secs = now - last_checkpoint_time; @@ -576,7 +578,7 @@ CheckpointerMain(void) rc = WaitLatch(&MyProc->procLatch, WL_LATCH_SET | WL_TIMEOUT | WL_POSTMASTER_DEATH, - cur_timeout * 1000L /* convert to ms */); + cur_timeout * 1000L /* convert to ms */ ); /* * Emergency bailout if postmaster has died. This is to avoid the @@ -687,8 +689,8 @@ CheckpointWriteDelay(int flags, double progress) return; /* - * Perform the usual duties and take a nap, unless we're behind - * schedule, in which case we just try to catch up as quickly as possible. + * Perform the usual duties and take a nap, unless we're behind schedule, + * in which case we just try to catch up as quickly as possible. */ if (!(flags & CHECKPOINT_IMMEDIATE) && !shutdown_requested && @@ -716,7 +718,8 @@ CheckpointWriteDelay(int flags, double progress) /* * This sleep used to be connected to bgwriter_delay, typically 200ms. * That resulted in more frequent wakeups if not much work to do. - * Checkpointer and bgwriter are no longer related so take the Big Sleep. + * Checkpointer and bgwriter are no longer related so take the Big + * Sleep. */ pg_usleep(100000L); } @@ -1017,7 +1020,7 @@ RequestCheckpoint(int flags) if (ntries >= 20) /* max wait 2.0 sec */ { elog((flags & CHECKPOINT_WAIT) ? ERROR : LOG, - "could not request checkpoint because checkpointer not running"); + "could not request checkpoint because checkpointer not running"); break; } } @@ -1130,9 +1133,9 @@ ForwardFsyncRequest(RelFileNodeBackend rnode, ForkNumber forknum, CheckpointerShmem->num_backend_writes++; /* - * If the checkpointer isn't running or the request queue is full, - * the backend will have to perform its own fsync request. But before - * forcing that to happen, we can try to compact the request queue. + * If the checkpointer isn't running or the request queue is full, the + * backend will have to perform its own fsync request. But before forcing + * that to happen, we can try to compact the request queue. */ if (CheckpointerShmem->checkpointer_pid == 0 || (CheckpointerShmem->num_requests >= CheckpointerShmem->max_requests && @@ -1339,8 +1342,8 @@ UpdateSharedMemoryConfig(void) SyncRepUpdateSyncStandbysDefined(); /* - * If full_page_writes has been changed by SIGHUP, we update it - * in shared memory and write an XLOG_FPW_CHANGE record. + * If full_page_writes has been changed by SIGHUP, we update it in shared + * memory and write an XLOG_FPW_CHANGE record. */ UpdateFullPageWrites(); @@ -1356,9 +1359,9 @@ FirstCallSinceLastCheckpoint(void) { /* use volatile pointer to prevent code rearrangement */ volatile CheckpointerShmemStruct *cps = CheckpointerShmem; - static int ckpt_done = 0; - int new_done; - bool FirstCall = false; + static int ckpt_done = 0; + int new_done; + bool FirstCall = false; SpinLockAcquire(&cps->ckpt_lck); new_done = cps->ckpt_done; |