Re: Clearing rows periodically - Mailing list pgsql-performance

From Andrew Sullivan
Subject Re: Clearing rows periodically
Date
Msg-id 20030718113439.GA2503@libertyrms.info
Whole thread Raw
In response to Clearing rows periodically  (Martin Foster <martin@ethereal-realms.org>)
List pgsql-performance
On Fri, Jul 18, 2003 at 12:55:12AM -0600, Martin Foster wrote:
> The other table follows a sequential order and carries more columns of
> information.   However, this table clears it's entry nightly and with
> current settings will delete roughly a days traffic sitting at 50K rows
> of information.

> has been skipped, which includes the use of VACUUM ANALYZE EXPLAIN.
> This seems to be an indication that the process of a daily delete is
> actually a very wise step to take, even if the information itself is not
> needed for very long.
>
> A VACUUM FULL will correct the issue, but put the site out of commission
> for roughly 20 minutes as the drive crunches the information.

During your "clearing period", why not do the deletes in batches, and
VACUUM the table periodically.  That will allow you to reclaim the
space gradually, and ensure that you don't end up with a big "bald
spot".  But you probably want to increase your FSM settings.  See the
docs.

A

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