OT: MySQL considerations (Was: Re: [rt-users] Performance Issues)

[Harald Wagener]

Am 09.09.2004 um 21:14 schrieb Dan Pritts:

> On Thu, Sep 09, 2004 at 02:50:26PM -0400, Jesse Vincent wrote:
>> Ok. That tells us that 1) you're running mysql in the default
>> configuration, which is optimized for a pentium 133 with 64 megs of 
>> RAM.
>> That's a bad plan.
>
> Nice.  But is this really the problem here with a db with 100 tickets?

The 'large' is about the system resources and database complexity, not 
necessarily the db size.  MySQL does file based operations if the 
memory limits configured have been reached. This * will * slow things 
down.
>
>> and 2) you missed the note that said that InnoDB is a
>> hard requirement. You _should_ see massively degraded performance if
>> you're running without it. And also, database corruption.
>
> Whoops.  I must have modified the my.cnf after installing RT.  I 
> probably
> did this to turn on skip-networking and copied the skip-innodb from
> another server without remembering it was necessary.
>
> However, i've turned it on, and restarted mysql, and there's no
> apparent effect.   Things still take a long time, and 
> mason_handler.fcgi
> processes still eat the CPU (visible via top) while I'm waiting for the
> web requests to be fulfilled.

You have to change the tables, too. They are in MyISAM format now. This 
is done in MySQL with  "ALTER TABLE whatevertable TYPE=innodb;". 
Turning on innodb support in the engine does not automatically convert 
Your database.

Regards,
     Harald