FreeBSD and MySQL - mysqld eats CPU alive

[somethrowawayaddy at d.sparks.net]

On Sat, 31 Jul 2004, adp wrote:

> I recently posted the following message to MySQL discussion list. The
> response there, and the one I keep finding on Google, is that this is a
> long-standing issue betweeen FreeBSD and MySQL. For me this has been
> happening since FreeBSD 4.4.

I had that problem a couple of years ago and resolved it on a box that's
still in use.  Very heavily loaded machine, 15 GB database, over 300
million rows in one table.  I couldn't find notes on it, however, and
don't recall exactly what it was.

One thing it might have been - did you change the HZ value in your kernel
conf file, perhaps for device polling?  I ran into problems on this
machine when setting HZ above 500 but don't recall for sure it was mysql
problems.

I'm happy to share the mysql build and conf files, and the kernel conf
file if you think it would help.  I think it was a kernel tweak that
solved the problem.

HTH,

--- David