Message-ID: <44915A9D.6090407@fuzzy.cz>
Date: Thu, 15 Jun 2006 15:03:25 +0200
From: Tomas Vondra <tv@fuzzy.cz>
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To: Mindaugas <mind@bi.lt>
CC: pgsql-performance@postgresql.org
Subject: Re: How to analyze function performance
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It depends what is the purpose of the function. If it's mainly a
container for a heap of SQL queries along with some simple IF, ELSE
etc. then I use two simple ways to analyze the performance (or lack
of performance):

1) I use a lot of debug messages

2) I print out all SQL and the execute EXPLAIN / EXPLAIN ANALYZE on them

If the function is mainly a computation of something, it's usually nice
to try to use for example C language, as it's much faster than PL/pgSQL
for this type of functions.

But it depends on what you are trying to do in that function ...

Tomas

>   Hello,
> 
>   Is it possible to somehow analyze function performance? E.g.
> we are using function cleanup() which takes obviously too much time
> to execute but I have problems trying to figure what is slowing things
> down.
> 
>   When I explain analyze function lines step by step it show quite
> acceptable performance.
> 
>   PostgreSQL 8.0 is running on two dual core Opterons.
> 
>   Thanks,
> 
>   Mindaugas