Re: configure option for XLOG_BLCKSZ - Mailing list pgsql-patches

From Alvaro Herrera
Subject Re: configure option for XLOG_BLCKSZ
Date
Msg-id 20080505150932.GD27548@alvh.no-ip.org
Whole thread Raw
In response to Re: configure option for XLOG_BLCKSZ  (Andreas 'ads' Scherbaum <adsmail@wars-nicht.de>)
Responses Re: configure option for XLOG_BLCKSZ
Re: configure option for XLOG_BLCKSZ
List pgsql-patches
Andreas 'ads' Scherbaum wrote:
> On Sat, 03 May 2008 13:14:35 -0400 Tom Lane wrote:
>
> > Simon Riggs <simon@2ndquadrant.com> writes:
> >
> > > Not seen any gains from varying the WAL file size since then...
> >
> > I think the use-case for varying the WAL segment size is unrelated to
> > performance of the master server, but would instead be concerned with
> > adjusting the granularity of WAL log shipping.
>
> *nod* I heard this argument several times. Simon: there was a discussion
> about this topic in Prato last year. Since WAL logfiles are usually
> binary stuff, the files can't be compressed much so a smaller logfile
> size on a not-so-much-used system would save a noticeable amount of
> bandwith (and cpu cycles for compression).

Seems the stuff to zero out the unused segment tail would be more useful
here.

Kevin sent me the source file some time ago -- he didn't want to upload
them to pgfoundry because he was missing a Makefile.  I built one for
him, but last time I looked he hadn't uploaded anything.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.

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