diff options
| author | Tom Lane | 2005-03-04 20:21:07 +0000 |
|---|---|---|
| committer | Tom Lane | 2005-03-04 20:21:07 +0000 |
| commit | 5d5087363d7cdbd00fc432a1216e83a00f7139bd (patch) | |
| tree | 56492be3beb9be188f37bfa68c9bfc0e35b0961c /src/backend/postmaster | |
| parent | 5592a6cf46d60187b6f4895d2144e67d4f54fa25 (diff) | |
Replace the BufMgrLock with separate locks on the lookup hashtable and
the freelist, plus per-buffer spinlocks that protect access to individual
shared buffer headers. This requires abandoning a global freelist (since
the freelist is a global contention point), which shoots down ARC and 2Q
as well as plain LRU management. Adopt a clock sweep algorithm instead.
Preliminary results show substantial improvement in multi-backend situations.
Diffstat (limited to 'src/backend/postmaster')
| -rw-r--r-- | src/backend/postmaster/bgwriter.c | 21 |
1 files changed, 9 insertions, 12 deletions
diff --git a/src/backend/postmaster/bgwriter.c b/src/backend/postmaster/bgwriter.c index 128122355b..09775bd32a 100644 --- a/src/backend/postmaster/bgwriter.c +++ b/src/backend/postmaster/bgwriter.c @@ -37,7 +37,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/postmaster/bgwriter.c,v 1.14 2005/02/19 23:16:15 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/postmaster/bgwriter.c,v 1.15 2005/03/04 20:21:06 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -116,9 +116,6 @@ static BgWriterShmemStruct *BgWriterShmem; * GUC parameters */ int BgWriterDelay = 200; -int BgWriterPercent = 1; -int BgWriterMaxPages = 100; - int CheckPointTimeout = 300; int CheckPointWarning = 30; @@ -274,7 +271,6 @@ BackgroundWriterMain(void) bool force_checkpoint = false; time_t now; int elapsed_secs; - int n; long udelay; /* @@ -365,16 +361,13 @@ BackgroundWriterMain(void) * checkpoints happen at a predictable spacing. */ last_checkpoint_time = now; - - /* Nap for configured time before rechecking */ - n = 1; } else - n = BufferSync(BgWriterPercent, BgWriterMaxPages); + BgBufferSync(); /* - * Nap for the configured time or sleep for 10 seconds if there - * was nothing to do at all. + * Nap for the configured time, or sleep for 10 seconds if there + * is no bgwriter activity configured. * * On some platforms, signals won't interrupt the sleep. To ensure * we respond reasonably promptly when someone signals us, break @@ -383,7 +376,11 @@ BackgroundWriterMain(void) * * We absorb pending requests after each short sleep. */ - udelay = ((n > 0) ? BgWriterDelay : 10000) * 1000L; + if ((bgwriter_all_percent > 0.0 && bgwriter_all_maxpages > 0) || + (bgwriter_lru_percent > 0.0 && bgwriter_lru_maxpages > 0)) + udelay = BgWriterDelay * 1000L; + else + udelay = 10000000L; while (udelay > 1000000L) { if (got_SIGHUP || checkpoint_requested || shutdown_requested) |