diff options
Diffstat (limited to 'src/backend/postmaster/pgstat.c')
| -rw-r--r-- | src/backend/postmaster/pgstat.c | 45 |
1 files changed, 32 insertions, 13 deletions
diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c index a192b4e5c87..d4a07efce2f 100644 --- a/src/backend/postmaster/pgstat.c +++ b/src/backend/postmaster/pgstat.c @@ -13,7 +13,7 @@ * * Copyright (c) 2001-2005, PostgreSQL Global Development Group * - * $PostgreSQL: pgsql/src/backend/postmaster/pgstat.c,v 1.118 2006/01/03 19:54:08 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/postmaster/pgstat.c,v 1.119 2006/01/04 21:06:31 tgl Exp $ * ---------- */ #include "postgres.h" @@ -147,6 +147,7 @@ static int pgStatNumBackends = 0; static volatile bool need_statwrite; + /* ---------- * Local function forward declarations * ---------- @@ -608,6 +609,9 @@ pgstat_start(void) /* Close the postmaster's sockets */ ClosePostmasterPorts(false); + /* Lose the postmaster's on-exit routines */ + on_exit_reset(); + /* Drop our connection to postmaster's shared memory, as well */ PGSharedMemoryDetach(); @@ -1465,9 +1469,6 @@ PgstatBufferMain(int argc, char *argv[]) MyProcPid = getpid(); /* reset MyProcPid */ - /* Lose the postmaster's on-exit routines */ - on_exit_reset(); - /* * Ignore all signals usually bound to some action in the postmaster, * except for SIGCHLD and SIGQUIT --- see pgstat_recvbuffer. @@ -1551,10 +1552,10 @@ PgstatCollectorMain(int argc, char *argv[]) fd_set rfds; int readPipe; int len = 0; - struct itimerval timeval; + struct itimerval timeout; HASHCTL hash_ctl; bool need_timer = false; - + MyProcPid = getpid(); /* reset MyProcPid */ /* @@ -1597,11 +1598,15 @@ PgstatCollectorMain(int argc, char *argv[]) init_ps_display("stats collector process", "", ""); set_ps_display(""); + /* + * Arrange to write the initial status file right away + */ need_statwrite = true; - MemSet(&timeval, 0, sizeof(struct itimerval)); - timeval.it_value.tv_sec = PGSTAT_STAT_INTERVAL / 1000; - timeval.it_value.tv_usec = PGSTAT_STAT_INTERVAL % 1000; + /* Preset the delay between status file writes */ + MemSet(&timeout, 0, sizeof(struct itimerval)); + timeout.it_value.tv_sec = PGSTAT_STAT_INTERVAL / 1000; + timeout.it_value.tv_usec = PGSTAT_STAT_INTERVAL % 1000; /* * Read in an existing statistics stats file or initialize the stats to @@ -1634,6 +1639,12 @@ PgstatCollectorMain(int argc, char *argv[]) */ for (;;) { + /* + * If time to write the stats file, do so. Note that the alarm + * interrupt isn't re-enabled immediately, but only after we next + * receive a stats message; so no cycles are wasted when there is + * nothing going on. + */ if (need_statwrite) { pgstat_write_statsfile(); @@ -1776,11 +1787,16 @@ PgstatCollectorMain(int argc, char *argv[]) */ pgStatNumMessages++; + /* + * If this is the first message after we wrote the stats file the + * last time, enable the alarm interrupt to make it be written + * again later. + */ if (need_timer) { - if (setitimer(ITIMER_REAL, &timeval, NULL)) + if (setitimer(ITIMER_REAL, &timeout, NULL)) ereport(ERROR, - (errmsg("unable to set statistics collector timer: %m"))); + (errmsg("could not set statistics collector timer: %m"))); need_timer = false; } } @@ -1806,6 +1822,7 @@ PgstatCollectorMain(int argc, char *argv[]) } +/* SIGALRM signal handler for collector process */ static void force_statwrite(SIGNAL_ARGS) { @@ -1913,8 +1930,10 @@ pgstat_recvbuffer(void) /* * Wait for some work to do; but not for more than 10 seconds. (This * determines how quickly we will shut down after an ungraceful - * postmaster termination; so it needn't be very fast.) struct timeout - * is modified by some operating systems. + * postmaster termination; so it needn't be very fast.) + * + * struct timeout is modified by select() on some operating systems, + * so re-fill it each time. */ timeout.tv_sec = 10; timeout.tv_usec = 0; |