Skip site navigation (1) Skip section navigation (2)

Re: Less rows -> better performance?

From: Andreas Hartmann <andreas(at)apache(dot)org>
To: pgsql-performance(at)postgresql(dot)org
Subject: Re: Less rows -> better performance?
Date: 2008-07-21 11:25:30
Message-ID: (view raw, whole thread or download thread mbox)
Lists: pgsql-performance
Richard, thanks for your reply!

Richard Huxton schrieb:
> Andreas Hartmann wrote:
>> Dear PostgreSQL community,
>> first some info about our application:
>> - Online course directory for a University
>> - Amount of data: complete dump is 27 MB
>> - Semester is part of primary key in each table
>> - Data for approx. 10 semesters stored in the DB
>> - Read-only access from web application (JDBC)
>> Our client has asked us if the performance of the application could be
>> improved by moving the data from previous years to a separate "archive"
>> application. 
> If you had 27GB of data maybe, but you've only got 27MB - that's 
> presumably all sitting in memory.

Here's some info about the actual amount of data:

SELECT pg_database.datname,
pg_size_pretty(pg_database_size(pg_database.datname)) AS size
FROM pg_database where pg_database.datname = 'vvz_live_1';

     datname    |  size
  vvz_live_1    | 2565 MB

I wonder why the actual size is so much bigger than the data-only dump - 
is this because of index data etc.?

> What in particular is slow?

There's no particular bottleneck (at least that we're aware of). During 
the first couple of days after the beginning of the semester the 
application request processing tends to slow down due to the high load 
(many students assemble their schedule). The customer upgraded the 
hardware (which already helped a lot), but they asked us to find further 
approaches to performance optimiziation.

-- Andreas

Andreas Hartmann, CTO
BeCompany GmbH
Tel.: +41 (0) 43 818 57 01

In response to


pgsql-performance by date

Next:From: Guillaume SmetDate: 2008-07-21 11:32:37
Subject: Re: Less rows -> better performance?
Previous:From: Valentin BogdanovDate: 2008-07-21 11:19:15
Subject: Perl/DBI vs Native

Privacy Policy | About PostgreSQL
Copyright © 1996-2017 The PostgreSQL Global Development Group