Message-ID: <433B4AA4.9080008@freedomcircle.net>
Date: Wed, 28 Sep 2005 22:00:04 -0400
From: Joe <svn@freedomcircle.net>
Organization: Freedom Circle, LLC
User-Agent: Mozilla Thunderbird 1.0 (Windows/20041206)
MIME-Version: 1.0
To: pgsql-performance@postgresql.org
Subject: Comparative performance
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit

I'm converting a relatively small database (2 MB) from MySQL to PostgreSQL.  It 
is used to generate web pages using PHP.  Although the actual website runs under 
Linux, the development is done under XP.  I've completed most of the data 
conversion and rewrite of the PHP scripts, so now I'm comparing relative 
performance.

It appears that PostgreSQL is two to three times slower than MySQL.  For 
example, some pages that have some 30,000 characters (when saved as HTML) take 1 
to 1 1/2 seconds with MySQL but 3 to 4 seconds with PostgreSQL.  I had read that 
the former was generally faster than the latter, particularly for simple web 
applications but I was hoping that Postgres' performance would not be that 
noticeably slower.

I'm trying to determine if the difference can be attributed to anything that 
I've done or missed.  I've run VACUUM ANALYZE on the two main tables and I'm 
looking at the results of EXPLAIN on the query that drives the retrieval of 
probably 80% of the data for the pages in question.

Before I post the EXPLAIN and the table schema I'd appreciate confirmation that 
this list is the appropriate forum.  I'm a relative newcomer to PostgreSQL (but 
not to relational databases), so I'm not sure if this belongs in the novice or 
general lists.

Joe