Re: XLOG_BLCKSZ vs. wal_buffers table - Mailing list pgsql-hackers

From Simon Riggs
Subject Re: XLOG_BLCKSZ vs. wal_buffers table
Date
Msg-id 1147375664.28245.53.camel@localhost.localdomain
Whole thread Raw
In response to Re: XLOG_BLCKSZ vs. wal_buffers table  (Mark Wong <markw@osdl.org>)
Responses Re: XLOG_BLCKSZ vs. wal_buffers table  (Mark Wong <markw@osdl.org>)
List pgsql-hackers
On Wed, 2006-05-10 at 09:55 -0700, Mark Wong wrote:
> Simon Riggs wrote:
> > Could you turn full_page_writes = off and do a few more tests? I think
> > the full page writes is swamping the xlog and masking the performance we
> > might see for normal small xlog writes.
> > I'd try XLOG_BLCKSZ = 4096 and 8192 to start with. Thanks.
> 
> Ok, got data for XLOG_BLCKXZ at 4096, 8192, and 32768 with
> full_page_wirtes = off.  The new data is at the bottom of the page:
>     http://developer.osdl.org/markw/pgsql/xlog_blcksz.html

Mark,

What do you think is causing the step changes at 30+ and 60+ minutes on
these tests?

--  Simon Riggs EnterpriseDB          http://www.enterprisedb.com



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