From: Tom Lane <tgl@sss.pgh.pa.us>
To: Sergio Gabriel Rodriguez <sgrodriguez@gmail.com>
cc: pgsql-performance@postgresql.org
Subject: Re: problems with large objects dump
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Comments: In-reply-to Sergio Gabriel Rodriguez <sgrodriguez@gmail.com>
	message dated "Thu, 20 Sep 2012 12:53:10 -0300"
Date: Thu, 20 Sep 2012 12:33:21 -0400
Message-ID: <24248.1348158801@sss.pgh.pa.us>

Sergio Gabriel Rodriguez <sgrodriguez@gmail.com> writes:
> On Thu, Sep 20, 2012 at 11:35 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> You wouldn't happen to be
>> trying to use a 9.0 or later pg_dump would you?  Exactly what 8.4.x
>> release is this, anyway?

> Tom, thanks for replying, yes, we tried it with postgres postgres 9.1 and
> 9.2 and the behavior is exactly the same. The production version is 8.4.9

Well, I see three different fixes for O(N^2) pg_dump performance
problems in the 8.4.x change logs since 8.4.9, so you're a bit behind
the times there.  However, all of those fixes would have been in 9.2.0,
so if you saw no improvement with a 9.2.0 pg_dump then the problem is
something else.  Can you put together a test case for somebody else to
try, or try to locate the bottleneck yourself using oprofile or perf?

			regards, tom lane