Bad performance in bulky updates

From: "Carlos H(dot) Reimer" <carlos(dot)reimer(at)opendb(dot)com(dot)br>
To: "Pgsql-General(at)Postgresql(dot)Org" <pgsql-general(at)postgresql(dot)org>
Subject: Bad performance in bulky updates
Date: 2006-10-31 01:51:30
Message-ID: PEEPKDFEHHEMKBBFPOOKAECIDGAA.carlos.reimer@opendb.com.br
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

Hi,

We have very bad performance issues in one of our customer PostgreSQL
servers and we would like some suggestions to improve the performance for
bulky updates.

When one of the biggest tables has all lines updated for example, it takes
at about 30 minutes for processing. If we drop all indexes (21) and let only
the primary index the same update takes 2 minutes.

As far as I could see there is no cpu nor memory bottleneck but sar is
indicating 50% of iowait during those update processings.

What I'm suggesting in priority order:

a) add another 2 SCSI disks and move index data to the new drives
b) add a SCSCI controllers with RAID support and move existing disks to the
new controller
c) add another disk and move pg_xlog to there

Server configuration data:
http://www.opendb.com.br/servidor.htm

Is there any other suggestion to improve the performance of those updates?

Thank you in advance!

Carlos

Responses

Browse pgsql-general by date

  From Date Subject
Next Message Tom Lane 2006-10-31 02:02:31 Re: Bad performance in bulky updates
Previous Message Ganbold 2006-10-31 01:50:00 Re: postgresql books and convertion utilities