diff options
Diffstat (limited to 'src/backend/postmaster/postmaster.c')
| -rw-r--r-- | src/backend/postmaster/postmaster.c | 71 |
1 files changed, 65 insertions, 6 deletions
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c index 01c3a363c8f..52c91fa97d9 100644 --- a/src/backend/postmaster/postmaster.c +++ b/src/backend/postmaster/postmaster.c @@ -37,7 +37,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/postmaster/postmaster.c,v 1.348 2003/11/11 01:09:42 momjian Exp $ + * $Header: /cvsroot/pgsql/src/backend/postmaster/postmaster.c,v 1.349 2003/11/19 15:55:07 wieck Exp $ * * NOTES * @@ -104,6 +104,7 @@ #include "storage/pg_shmem.h" #include "storage/pmsignal.h" #include "storage/proc.h" +#include "storage/bufmgr.h" #include "access/xlog.h" #include "tcop/tcopprot.h" #include "utils/guc.h" @@ -224,7 +225,8 @@ char *preload_libraries_string = NULL; /* Startup/shutdown state */ static pid_t StartupPID = 0, ShutdownPID = 0, - CheckPointPID = 0; + CheckPointPID = 0, + BgWriterPID = 0; static time_t checkpointed = 0; #define NoShutdown 0 @@ -298,6 +300,7 @@ __attribute__((format(printf, 1, 2))); #define StartupDataBase() SSDataBase(BS_XLOG_STARTUP) #define CheckPointDataBase() SSDataBase(BS_XLOG_CHECKPOINT) +#define StartBackgroundWriter() SSDataBase(BS_XLOG_BGWRITER) #define ShutdownDataBase() SSDataBase(BS_XLOG_SHUTDOWN) @@ -1056,6 +1059,17 @@ ServerLoop(void) } /* + * If no background writer process is running and we should + * do background writing, start one. It doesn't matter if + * this fails, we'll just try again later. + */ + if (BgWriterPID == 0 && BgWriterPercent > 0 && + Shutdown == NoShutdown && !FatalError && random_seed != 0) + { + BgWriterPID = StartBackgroundWriter(); + } + + /* * Wait for something to happen. */ memcpy((char *) &rmask, (char *) &readmask, sizeof(fd_set)); @@ -1478,6 +1492,13 @@ processCancelRequest(Port *port, void *pkt) backendPID))); return; } + else if (backendPID == BgWriterPID) + { + ereport(DEBUG2, + (errmsg_internal("ignoring cancel request for bgwriter process %d", + backendPID))); + return; + } else if (ExecBackend) AttachSharedMemoryAndSemaphores(); @@ -1660,6 +1681,13 @@ SIGHUP_handler(SIGNAL_ARGS) SignalChildren(SIGHUP); load_hba(); load_ident(); + + /* + * Tell the background writer to terminate so that we + * will start a new one with a possibly changed config + */ + if (BgWriterPID != 0) + kill(BgWriterPID, SIGTERM); } PG_SETMASK(&UnBlockSig); @@ -1692,6 +1720,8 @@ pmdie(SIGNAL_ARGS) * * Wait for children to end their work and ShutdownDataBase. */ + if (BgWriterPID != 0) + kill(BgWriterPID, SIGTERM); if (Shutdown >= SmartShutdown) break; Shutdown = SmartShutdown; @@ -1724,6 +1754,8 @@ pmdie(SIGNAL_ARGS) * abort all children with SIGTERM (rollback active transactions * and exit) and ShutdownDataBase when they are gone. */ + if (BgWriterPID != 0) + kill(BgWriterPID, SIGTERM); if (Shutdown >= FastShutdown) break; ereport(LOG, @@ -1770,6 +1802,8 @@ pmdie(SIGNAL_ARGS) * abort all children with SIGQUIT and exit without attempt to * properly shutdown data base system. */ + if (BgWriterPID != 0) + kill(BgWriterPID, SIGQUIT); ereport(LOG, (errmsg("received immediate shutdown request"))); if (ShutdownPID > 0) @@ -1877,6 +1911,12 @@ reaper(SIGNAL_ARGS) CheckPointPID = 0; checkpointed = time(NULL); + if (BgWriterPID == 0 && BgWriterPercent > 0 && + Shutdown == NoShutdown && !FatalError && random_seed != 0) + { + BgWriterPID = StartBackgroundWriter(); + } + /* * Go to shutdown mode if a shutdown request was pending. */ @@ -1983,6 +2023,8 @@ CleanupProc(int pid, GetSavedRedoRecPtr(); } } + else if (pid == BgWriterPID) + BgWriterPID = 0; else pgstat_beterm(pid); @@ -1996,6 +2038,7 @@ CleanupProc(int pid, { LogChildExit(LOG, (pid == CheckPointPID) ? gettext("checkpoint process") : + (pid == BgWriterPID) ? gettext("bgwriter process") : gettext("server process"), pid, exitstatus); ereport(LOG, @@ -2044,6 +2087,10 @@ CleanupProc(int pid, CheckPointPID = 0; checkpointed = 0; } + else if (pid == BgWriterPID) + { + BgWriterPID = 0; + } else { /* @@ -2754,6 +2801,8 @@ CountChildren(void) } if (CheckPointPID != 0) cnt--; + if (BgWriterPID != 0) + cnt--; return cnt; } @@ -2827,6 +2876,9 @@ SSDataBase(int xlop) case BS_XLOG_CHECKPOINT: statmsg = "checkpoint subprocess"; break; + case BS_XLOG_BGWRITER: + statmsg = "bgwriter subprocess"; + break; case BS_XLOG_SHUTDOWN: statmsg = "shutdown subprocess"; break; @@ -2883,6 +2935,10 @@ SSDataBase(int xlop) ereport(LOG, (errmsg("could not fork checkpoint process: %m"))); break; + case BS_XLOG_BGWRITER: + ereport(LOG, + (errmsg("could not fork bgwriter process: %m"))); + break; case BS_XLOG_SHUTDOWN: ereport(LOG, (errmsg("could not fork shutdown process: %m"))); @@ -2895,19 +2951,22 @@ SSDataBase(int xlop) /* * fork failure is fatal during startup/shutdown, but there's no - * need to choke if a routine checkpoint fails. + * need to choke if a routine checkpoint or starting a background + * writer fails. */ if (xlop == BS_XLOG_CHECKPOINT) return 0; + if (xlop == BS_XLOG_BGWRITER) + return 0; ExitPostmaster(1); } /* * The startup and shutdown processes are not considered normal - * backends, but the checkpoint process is. Checkpoint must be added - * to the list of backends. + * backends, but the checkpoint and bgwriter processes are. + * They must be added to the list of backends. */ - if (xlop == BS_XLOG_CHECKPOINT) + if (xlop == BS_XLOG_CHECKPOINT || xlop == BS_XLOG_BGWRITER) { if (!(bn = (Backend *) malloc(sizeof(Backend)))) { |