Subject: Re: Backup causing poor performance - suggestions
From: Simon Riggs <simon@2ndquadrant.com>
To: Craig James <craig_james@emolecules.com>
Cc: "Campbell, Lance" <lance@uiuc.edu>, pgsql-performance@postgresql.org
In-Reply-To: <481F3168.8050600@emolecules.com>
References: <B10E6810AC2A2F4EA7550D072CDE8760CDDD2C@SAB-FENWICK.sab.uiuc.edu>
	<481F3168.8050600@emolecules.com>
Content-Type: text/plain
Date: Mon, 05 May 2008 18:43:52 +0100
Message-Id: <1210009432.4435.102.camel@ebony.site>
Mime-Version: 1.0
Content-Transfer-Encoding: 7bit

On Mon, 2008-05-05 at 09:10 -0700, Craig James wrote:
> Campbell, Lance wrote:
> > We currently backup all of our database tables per schema using pg_dump 
> > every half hour.  We have been noticing that the database performance 
> > has been very poor during the backup process.  How can I improve the 
> > performance?
> 
> It sounds like the goal is to have frequent, near-real-time backups of
> your databases for recovery purposes.  Maybe instead of looking at
> pg_dump's performance, a better solution would be a replication system
> such as Slony, or a "warm backup" using Skype Tools.
> 
> Backing up the database every half hour puts a large load on the
> system during the dump, and means you are re-dumping the same data, 48
> times per day.  If you use a replication solution, the backup process
> is continuous (spread out through the day), and you're not re-dumping
> static data; the only data that moves around is the new data.
> 
> I've used Slony with mixed success; depending on the complexity and
> size of your database, it can be quite effective.  I've heard very
> good reports about Skype Tools, which has both a Slony-like replicator
> (not as configurable as Slony, but easier to set up and use), plus an
> entirely separate set of scripts that simplifies "warm standby" using
> WAL logging.

I think we should mention Warm Standby via pg_standby, which is part of
core software and documentation. Seems strange not to mention it at all.

-- 
  Simon Riggs
  2ndQuadrant  http://www.2ndQuadrant.com