Message-ID: <4CC714AA.20204@agliodbs.com>
Date: Tue, 26 Oct 2010 10:49:30 -0700
From: Josh Berkus <josh@agliodbs.com>
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To: Fujii Masao <masao.fujii@gmail.com>
CC: pgsql-hackers@postgresql.org
Subject: Re: Simplifying replication
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> What happens if max_wal_size is less than checkpoint_segments?
> Currently a checkpoint tries to leave WAL files which were generated
> from the prior ckpt start to current ckpt end. Because those WAL files
> are required for crash recovery. But we should delete some of them
> according to max_wal_size?

The ideas is that max_wal_size would *replace* checkpoint_segments.  The
checkpoint_segments setting is baffling to most PG DBAs.

-- 
                                  -- Josh Berkus
                                     PostgreSQL Experts Inc.
                                     http://www.pgexperts.com