From: Mario Splivalo <mario.splivalo@megafon.hr>
To: pgsql-performance@postgresql.org
Subject: Re: Different query plans on same servers
Date: Wed, 07 Dec 2011 10:34:56 +0100
Message-ID: <4EDF3340.1030403@megafon.hr> (raw)
In-Reply-To: <14289.1323201649@sss.pgh.pa.us>
References: <4EDE717A.9050604@megafon.hr>
<14289.1323201649@sss.pgh.pa.us>
On 12/06/2011 09:00 PM, Tom Lane wrote:
> Mario Splivalo <mario.splivalo@megafon.hr> writes:
>> I have 8.4.8 on producion and 8.4.9 on test, could that explain the
>> difference in plans chosen?
>
> I'd wonder first if you have the same statistics settings on both.
> The big problem here is that the estimation of the join size is bad
> (8588 versus 0).
Just an update here. I did downgrade postgres on testbox to 8.4.8 and
now it's choosing bad plan there too.
So we upgraded postgres on production server and the bad plan went away.
We're preparing for upgrade to 9.1 now, we hope to offload some of the
SELECTs to the slave server, we'll see how that will work.
Thank you for your inputs!
Mario
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-performance@postgresql.org
Cc: mario.splivalo@megafon.hr
Subject: Re: Different query plans on same servers
In-Reply-To: <4EDF3340.1030403@megafon.hr>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox