Date: Fri, 22 Feb 2013 08:37:23 -0500
From: Stephen Frost <sfrost@snowman.net>
To: Markus Schulz <msc@antzsystem.de>
Cc: pgsql-performance@postgresql.org
Subject: Re: BUG: endless lseek(..,
 SEEK_END) from select queries on x64 builds
Message-ID: <20130222133723.GR16142@tamriel.snowman.net>
References: <201302220925.26460.msc@antzsystem.de>
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Markus,

* Markus Schulz (msc@antzsystem.de) wrote:
> as you can see the query runs fine.=20
> I can run this query from a bash-psql-while-loop/jdbc-cli-tool=20
> endless without any problems.=20
> so far so good.
[...]
> JBoss EAP 5.1.2 with connection pooling and xa-datasource/two-phase-commi=
ts=20
> (transactions on multiple datasources needed)
> *and* *<prepared-statement-cache-size>1000</prepared-statement-cache-size=
>*
>=20
> i can run the query four times with good performance and after that postg=
resql=20
> starts with the strange lseek() behavior.=20

It sounds like your bash script and JBoss are doing something different.
Would it be possible for you to turn on log_statements =3D 'all' in PG,
see what's different, and then update the bash/psql script to do exactly
what JBoss does, and see if you can reproduce it that way?

It certainly looks like a PG bug, but it'd be a lot easier to debug with
a simple, well-defined test case which shows the failure.

	Thanks!

		Stephen

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