Horton

Re: Cost of XLogInsert CRC calculations

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Simon Riggs <simon@2ndquadrant.com>
Cc: Greg Stark <gsstark@mit.edu>, Mark Cave-Ayland <m.cave-ayland@webbased.co.uk>, "'Manfred Koizar'" <mkoi-pg@aon.at>, "'Bruce Momjian'" <pgman@candle.pha.pa.us>, pgsql-hackers@postgresql.org
Date: 2005-06-01T14:05:13Z
Lists: pgsql-hackers 
Simon Riggs <simon@2ndquadrant.com> writes:
> If I/O is a problem, then surely you will agree that PreAllocXLog is
> still required and should not be run by a backend?

It is still required, but it isn't run by backends --- it's fired off
during checkpoints.  I think there was some discussion recently about
making it more aggressive about allocating future segments; which
strikes me as a good idea.

			regards, tom lane