X-Original-To: pgsql-performance-postgresql.org@postgresql.org Received: from localhost (wm.hub.org [200.46.204.128]) by postgresql.org (Postfix) with ESMTP id E2EEF9FA47F; Fri, 21 Jul 2006 10:57:06 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.128]) (amavisd-new, port 10024) with ESMTP id 48046-01; Fri, 21 Jul 2006 13:56:57 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey- X-Greylist: from auto-whitelisted by SQLgrey- Received: from noel.decibel.org (noel.decibel.org [67.100.216.10]) by postgresql.org (Postfix) with ESMTP id 61A159FA42F; Fri, 21 Jul 2006 10:56:57 -0300 (ADT) Received: by noel.decibel.org (Postfix, from userid 1001) id A77CA56442; Fri, 21 Jul 2006 08:56:55 -0500 (CDT) Received: (hashcash-sendmail, from uid 1001); Fri, 21 Jul 2006 08:56:53 -0500 Date: Fri, 21 Jul 2006 08:56:53 -0500 From: "Jim C. Nasby" To: Robert Lor Cc: Tom Lane , Tatsuo Ishii , pgsql-hackers@postgresql.org, pgsql-performance@postgresql.org Subject: Re: [HACKERS] Sun Donated a Sun Fire T2000 to the PostgreSQL Message-ID: <20060721135653.GC83250@pervasive.com> References: <20060617.101521.95879771.t-ishii@sraoss.co.jp> <10226.1150511655@sss.pgh.pa.us> <20060617.111838.39487910.t-ishii@sraoss.co.jp> <20060713.180234.45872055.t-ishii@sraoss.co.jp> <8669.1153422118@sss.pgh.pa.us> <44C088C8.9050303@sun.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <44C088C8.9050303@sun.com> X-Operating-System: FreeBSD 6.0-RELEASE-p4 amd64 X-Distributed: Join the Effort! http://www.distributed.net User-Agent: Mutt/1.5.11 X-Hashcash: 1:20:060721:robert.lor@sun.com::RmmqtR1/hadFr7x6:0000000000000000000 0000000000000000000000006SsD X-Hashcash: 1:20:060721:tgl@sss.pgh.pa.us::yiT5BXP2TxNu6GHX:00000000000000000000 0000000000000000000000001zdk X-Hashcash: 1:20:060721:ishii@sraoss.co.jp::ENpbCfbgvkycw+dt:0000000000000000000 0000000000000000000000001G2y X-Hashcash: 1:20:060721:pgsql-hackers@postgresql.org::qeFxjM7zcA9+Okgh:000000000 0000000000000000000000003tHY X-Hashcash: 1:20:060721:pgsql-performance@postgresql.org::mDDPQyhP/oQ4bhwD:00000 0000000000000000000000003A8O X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0 tagged_above=0 required=5 tests= X-Spam-Level: X-Archive-Number: 200607/208 X-Sequence-Number: 20068 On Fri, Jul 21, 2006 at 12:56:56AM -0700, Robert Lor wrote: > I ran pgbench and fired up a DTrace script using the lwlock probes we've > added, and it looks like BufMappingLock is the most contended lock, but > CheckpointStartLocks are held for longer duration! Not terribly surprising given that that lock can generate a substantial amount of IO (though looking at the numbers, you might want to make bgwriter more aggressive). Also, that's a shared lock, so it won't have nearly the impact that BufMappingLock does. > Lock Id Mode Count > ControlFileLock Exclusive 1 > SubtransControlLock Exclusive 1 > BgWriterCommLock Exclusive 6 > FreeSpaceLock Exclusive 6 > FirstLockMgrLock Exclusive 48 > BufFreelistLock Exclusive 74 > BufMappingLock Exclusive 74 > CLogControlLock Exclusive 184 > XidGenLock Exclusive 184 > CheckpointStartLock Shared 185 > WALWriteLock Exclusive 185 > ProcArrayLock Exclusive 368 > CLogControlLock Shared 552 > SubtransControlLock Shared 1273 > WALInsertLock Exclusive 1476 > XidGenLock Shared 1842 > ProcArrayLock Shared 3160 > SInvalLock Shared 3684 > BufMappingLock Shared 14578 > > Lock Id Combined Time (ns) > ControlFileLock 7915 > BgWriterCommLock 43438 > FreeSpaceLock 111139 > BufFreelistLock 448530 > FirstLockMgrLock 2879957 > CLogControlLock 4237750 > SubtransControlLock 6378042 > XidGenLock 9500422 > WALInsertLock 16372040 > SInvalLock 23284554 > ProcArrayLock 32188638 > BufMappingLock 113128512 > WALWriteLock 142391501 > CheckpointStartLock 4171106665 > > > Regards, > -Robert > > > > ---------------------------(end of broadcast)--------------------------- > TIP 4: Have you searched our list archives? > > http://archives.postgresql.org > -- Jim C. Nasby, Sr. Engineering Consultant jnasby@pervasive.com Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461