Date: Mon, 28 Apr 2008 13:39:39 -0400 (EDT)
From: Greg Smith <gsmith@gregsmith.com>
To: Gauri Kanekar <meetgaurikanekar@gmail.com>
cc: pgsql-performance@postgresql.org
Subject: Re: Replication Syatem
In-Reply-To: <7e4ba9550804280705q43c51e66l104a5ff9272bbd4d@mail.gmail.com>
Message-ID: <Pine.GSO.4.64.0804281319180.14083@westnet.com>
References: <7e4ba9550804280638ie81dc23w472785c83cd38fcf@mail.gmail.com>
	<a2de01dd0804280658t68ac22dsf182d304a94de5a2@mail.gmail.com>
	<7e4ba9550804280705q43c51e66l104a5ff9272bbd4d@mail.gmail.com>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed

On Mon, 28 Apr 2008, Gauri Kanekar wrote:

> We are doing vacuum full every alternate day. We also do vacuum analyze 
> very often. We are currently using 8.1.3 version...Have already tried 
> all the option listed by you, thats y we reached to the decision of 
> having a replication sytsem.

Andrew Sullivan has already given a response here I agree with, I wanted 
to expland on that.  You have a VACUUM problem.  The fact that you need 
(or feel you need) to VACUUM FULL every other day says there's something 
very wrong here.  The way to solve most VACUUM problems is to VACUUM more 
often, so that the work in each individual one never gets so big that your 
system takes an unnaceptable hit, and you shouldn't ever need VACUUM FULL. 
Since your problem is being aggrevated because you're running a 
dangerously obsolete version, that's one of the first things you should 
fix--to at least the latest 8.1 if you can't deal with a larger version 
migration.  The fact that you're happily running 8.1.3 says you most 
certainly haven't tried all the other options here.

Every minute you spend looking into a replication system is wasted time 
you could be spending on the right fix here.  You've fallen into the 
common trap where you're fixated on a particular technical solution so 
much that you're now ignoring suggestions on how to resolve the root 
problem.  Replication is hard to get going even on a system that works 
perfectly, and replicating a known buggy system just to work around a 
problem really sounds like a bad choice.

--
* Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD