Re: WAL log archive frequency

Tom Lane wrote:
> Chris Jewell <c.jewell@lancaster.ac.uk> writes:
> > Further to my question on PITR, I have now implemented it :-)  However,
> > I was wondering about the frequency of archiving the WAL.  Does
> > postgresql wait until the current WAL file has reached 16MB before
> > calling the archive_command?
>
> Yes.  The assumption is the archive_command may be too stupid to deal
> with archiving the same file more than once, and/or might have
> performance issues with doing that, eg, if it's writing to tape or some
> kind of write-once media.
>
> You can do something like saving the newest-by-timestamp file in the
> xlog directory every minute or whatever via a cron job.  This ought to
> be better integrated though ...

FYI, this is documented.

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