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Message-ID: <46D546FC.9070308@enterprisedb.com>
Date: Wed, 29 Aug 2007 11:14:20 +0100
From: "Heikki Linnakangas" <heikki@enterprisedb.com>
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To: "Kari Lavikka" <tuner@bdb.fi>
Cc: <pgsql-performance@postgresql.org>
Subject: Re: Performance problem with table containing a lot of text (blog)
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Kari Lavikka wrote:
> On Wed, 29 Aug 2007, Heikki Linnakangas wrote:
> 
>> The idea of being able to set the toast threshold per column was
>> discussed during 8.3 development, but no patch was produced IIRC. We
>> might do that in the future. If you're willing to compile from source,
>> you can lower TOAST_TUPLE_THRESHOLD.
> 
> We are currently using Postgres 8.1 but have to upgrade to 8.2 shortly.
> New version fixes some vacuum problems.
> 
> I always compile postgres from source. Maybe I have to do some
> calculations because that setting affects all tables and databases. Most
> of our text/varchar columns are quite short but setting the threshold
> too low causes excessive seeks to toast tables... right?

Right. If you have trouble finding the right balance, you can also use
ALTER STORAGE PLAIN to force the other columns not to be toasted.

-- 
  Heikki Linnakangas
  EnterpriseDB   http://www.enterprisedb.com