Re: pgsql: Reduce checkpoints and WAL traffic on low activity database serv

On Wed, Nov 2, 2011 at 11:39 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> Reduce checkpoints and WAL traffic on low activity database server
> Previously, we skipped a checkpoint if no WAL had been written since
> last checkpoint, though this does not appear in user documentation.
> As of now, we skip a checkpoint until we have written at least one
> enough WAL to switch the next WAL file. This greatly reduces the
> level of activity and number of WAL messages generated by a very
> low activity server. This is safe because the purpose of a checkpoint
> is to act as a starting place for a recovery, in case of crash.
> This patch maintains minimal WAL volume for replay in case of crash,
> thus maintaining very low crash recovery time.

I think you need to update the docs, for checkpoint_timeout if nothing else.

--
Robert Haas
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