Re: pg_start_backup and pg_stop_backup Re: Re: [COMMITTERS] pgsql: Make CheckRequiredParameterValues() depend upon correct
Simon Riggs <simon@2ndquadrant.com>
From: Simon Riggs <simon@2ndQuadrant.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Bruce Momjian <bruce@momjian.us>, Tom Lane <tgl@sss.pgh.pa.us>, Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>, Fujii Masao <masao.fujii@gmail.com>, Alvaro Herrera <alvherre@commandprompt.com>, Josh Berkus <josh@agliodbs.com>, pgsql-hackers@postgresql.org
Date: 2010-04-30T18:08:25Z
Lists: pgsql-hackers
On Fri, 2010-04-30 at 13:52 -0400, Robert Haas wrote: > On Fri, Apr 30, 2010 at 1:44 PM, Simon Riggs <simon@2ndquadrant.com> wrote: > > On Fri, 2010-04-30 at 12:22 -0400, Bruce Momjian wrote: > >> > > >> > (wal_keep_segments can be changed without restarting, right?) > >> > >> Should we allow -1 to mean "keep all segments"? > > > > Why is that not called "max_wal_segments"? wal_keep_segments sounds like > > its been through Google translate. > > Because it's not a maximum? I see the thinking, but why would you ever set it to be something that is *less* than the existing numbers? That would be pointless and indeed, does nothing. The only time you touch it at all is when you set it to be a value higher than the number of files that would normally be kept, and when that is the case it *will* be the maximum. So I say, max_wal_segments = 0 (default) meaning no limit, we just rotate as needed. We put a comment in the docs to say that if a value is selected less than 2*checkpoint_segments+1 then the value is overridden. -- Simon Riggs www.2ndQuadrant.com