Date: Fri, 10 Jul 2015 12:44:25 +0200
From: Andres Freund <andres@anarazel.de>
To: Heikki Linnakangas <hlinnaka@iki.fi>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Fujii Masao <masao.fujii@gmail.com>,
 Martijn van Oosterhout <kleptog@svana.org>,
 PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: WAL logging problem in 9.4.3?
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On 2015-07-10 13:38:50 +0300, Heikki Linnakangas wrote:
> In the long-term, I'd like to refactor this whole thing so that we never
> WAL-log any operations on a relation that's created in the same transaction
> (when wal_level=minimal). Instead, at COMMIT, we'd fsync() the relation, or
> if it's smaller than some threshold, WAL-log the contents of the whole file
> at that point. That would move all that
> more-difficult-than-it-seems-at-first-glance logic from COPY and indexam's
> to a central location, and it would allow the same optimization for all
> operations, not just COPY. But that probably isn't feasible to backpatch.

I don't think that's really realistic until we have a buffer manager
that lets you efficiently scan for all pages of a relation :(


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