Re: Backups from the standby (Incrementally Updated Backups), open item - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: Backups from the standby (Incrementally Updated Backups), open item
Date
Msg-id 201008252356.o7PNuqu02225@momjian.us
Whole thread Raw
In response to Re: Backups from the standby (Incrementally Updated Backups), open item  (Simon Riggs <simon@2ndQuadrant.com>)
List pgsql-hackers
Simon Riggs wrote:
> On Tue, 2010-08-24 at 11:04 -0700, Josh Berkus wrote:
> 
> > I've been looking at the open item which belongs with this doc:
> > 
> > http://www.postgresql.org/docs/9.0/static/backup-incremental-updated.html
> 
> I'm back from holidays today, so will begin looking at this and related
> open-ish items.

I talked to several people on IM about this today and there was general
agreement that the procedure as outlined, and even as proposed with
pg_start_backup(), is not known to be reliable enough to put in our
docs.

I have therefore removed it from the 9.0 docs, and created a wiki for
it:
http://wiki.postgresql.org/wiki/Incrementally_Updated_Backups

I looked at the 8.4 doc mention:
http://www.postgresql.org/docs/8.4/static/warm-standby.html#BACKUP-INCREMENTAL-UPDATED

and it was sufficiently vague that no one has obviously implemented it
or we would have gotten complaints that it does not work, so I am not
sure about removing all previous mentions.  I think the fact it might
work with full page writes allows it to work, but it is not something we
do not want to continue recommending.

If we get enough research that the wiki-listed procedure is good, we can
move it back into the docs.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + It's impossible for everything to be true. +


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