Re: performance with triggers depends on table size?

On Mon, Aug 12, 2002 at 06:21:05PM -0400, Tom Lane wrote:

> Perhaps what it's actually dependent on is the size of the stats table?
> Do you have indexes on the stats table, and if so are they being used
> by the trigger's queries?

I started the insert on the real database to copy some 3.6 million records
between the tables, and plotted the timings -- now (with about half a
million records done) you can see the time it takes to insert a row
actually goes in a sawtooth pattern -- cf.
http://www.coretec.at/~cm/insert-trigger.gif
which has msec/inserted row on the Y axis and number of rows in the
"output" table on the X axis.

Can anybody explain this?

Note that these are not the tables from the perl script I posted, but
something more complex with a few foreign key constraints, but the
trigger is basically doing the same thing.

Oh, and:

=> select version();
                            version
---------------------------------------------------------------
 PostgreSQL 7.2.1 on i686-pc-linux-gnu, compiled by GCC 2.95.4

on Debian/Stable (3.0).

Regards,

cm.

--
Christian Mock                          Wiedner Hauptstrasse 15
Senior Security Engineer                1040 Wien
CoreTEC IT Security Solutions GmbH      +43-1-5037273