Horton

Re: Streaming a base backup from master

Robert Haas <robertmhaas@gmail.com>

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From: Robert Haas <robertmhaas@gmail.com>
To: Greg Stark <gsstark@mit.edu>
Cc: Martijn van Oosterhout <kleptog@svana.org>, Stephen Frost <sfrost@snowman.net>, Dave Page <dpage@pgadmin.org>, Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>, Magnus Hagander <magnus@hagander.net>
Date: 2010-09-06T22:09:50Z
Lists: pgsql-hackers 
On Mon, Sep 6, 2010 at 10:07 AM, Greg Stark <gsstark@mit.edu> wrote:
> I think that description pretty much settles the question in my mind.
> The implementation choice of scanning the WAL to find all the changed
> blocks is more relevant to the use cases where incremental backups are
> useful. If you still have to read the entire database then there's not
> all that much to be gained except storage space. If you scan the WAL
> then you can avoid reading most of your large data warehouse to
> generate the incremental and only read the busy portion.

If you can scan the WAL, why wouldn't you just replay it?

-- 
Robert Haas
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