Re: vacuum a lot of data when insert only

From: Andrew Sullivan <ajs(at)crankycanuck(dot)ca>
To: pgsql-performance(at)postgresql(dot)org
Subject: Re: vacuum a lot of data when insert only
Date: 2007-06-21 17:17:33
Message-ID: 20070621171733.GD5500@phlogiston.dyndns.org
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On Thu, Jun 21, 2007 at 07:53:54PM +0300, Sabin Coanda wrote:
> Reading different references, I understand there is no need to vacuum a
> table where just insert actions perform.

That's false. First, you must vacuum at least once every 2 billion
transactions. Second, if a table is INSERTed to, but then the
INSERTing transaction rolls back, it leaves a dead tuple in its wake.
My guess, from your posted example, is that you have the latter case
happening, because you have removable rows (that's assuming you
aren't mistaken that there's never a delete or update to the table).

A

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Andrew Sullivan | ajs(at)crankycanuck(dot)ca
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