From: Jim C. Nasby <jnasby@pervasive.com>
To: Greg Stark <gsstark@mit.edu>
Cc: Brendan Duddridge <brendan@clickspace.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>
Cc: PostgreSQL Performance <pgsql-performance@postgresql.org>
Subject: Re: App very unresponsive while performing simple update
Date: Wed, 31 May 2006 22:18:05 -0500
Message-ID: <20060601031805.GI53487@pervasive.com> (raw)
In-Reply-To: <874pz6jjze.fsf@stark.xeocode.com>
References: <961F6F02-4B00-494C-B071-6DF76A305C14@clickspace.com>
<21B15664-F4EE-462C-88B4-EEEB2B4A979F@clickspace.com>
<874pzanvk6.fsf@stark.xeocode.com>
<17733.1148832292@sss.pgh.pa.us>
<3C756C36-DC66-4D13-B2CE-99CFCE7BF390@clickspace.com>
<87hd39n3c4.fsf@stark.xeocode.com>
<20060531062307.GG53487@pervasive.com>
<874pz6jjze.fsf@stark.xeocode.com>
On Wed, May 31, 2006 at 11:24:05AM -0400, Greg Stark wrote:
> stark=> begin;
> BEGIN
> stark=> begin;
> BEGIN
> stark=> update t1 set a = 0;
> UPDATE 1
> stark=> update t1 set a = 1;
> UPDATE 1
>
> stark=> update t2 set b = 0;
> UPDATE 1
> stark=> update t2 set b = 2;
> UPDATE 1
> stark=> commit;
> stark=> commit;
> ERROR: deadlock detected
> DETAIL: Process 16531 waits for ShareLock on transaction 245131; blocked by process 16566
> Process 16566 waits for ShareLock on transaction 245132; blocked by process 16531.
> CONTEXT: SQL statement "SELECT 1 FROM ONLY "public"."t1" x WHERE "a" = $1 FOR SHARE OF x"
> stark=> >
> COMMIT
I tried duplicating this but couldn't. What's the data in the tables?
--
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
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To: pgsql-performance@postgresql.org
Cc: jnasby@pervasive.com, gsstark@mit.edu, brendan@clickspace.com, tgl@sss.pgh.pa.us
Subject: Re: App very unresponsive while performing simple update
In-Reply-To: <20060601031805.GI53487@pervasive.com>
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