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Subject: Re: Added documentation about caching, reliability
From: Simon Riggs <simon@2ndquadrant.com>
To: Bruce Momjian <pgman@candle.pha.pa.us>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>,
	PostgreSQL-documentation <pgsql-docs@postgresql.org>
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Organization: 2nd Quadrant
Date: Sun, 09 Oct 2005 09:54:42 +0100
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On Wed, 2005-09-28 at 14:26 -0400, Bruce Momjian wrote:
> I have added a section to the top of the WAL docs explaining caching and
> reliability issues:
> 
> 	http://candle.pha.pa.us/main/writings/pgsql/sgml/reliability.html
> 
> I also renamed the chapter "Reilability" rather than "WAL."
> 

I submitted a patch last week that builds further on Bruce's changes.
[Docs for PITR and full_page_writes interaction, 2 Oct]

The patch includes:

1. Minor rewording of the case that Bruce refers to "recovery" and I
have differentiated the cases of crash recovery and PITR. The
corresponding section of the backup chapter has also been changed to
include a short discussion on full_page_writes and WAL compression, with
a link back to the WAL section.

2. Merged the 1st and 2nd sects of Reliability into a single section.
The 1st section was only a single paragraph and so that improves
readability. I've freshened that section, since it has not been updated
since 7.1 and currently still reads as if WAL has just been released.

3. I've updated the section on WAL configuration with further WAL
related comments and clarifications. These relate to full_page_writes
and appropriate settings of wal_buffers to match.

Best Regards, Simon Riggs