Subject Re: High processor usage FB 1.5.0
Author Adam
> I've been asked to support a Firebird application currently running on
> FB 1.5.0. It's being run on a dual processor Xeon 3.0Ghz with 1Gb
> memory and Win 2k server.
> Currently it's having performance issues where the server is ~50% of
> the time running at 100% off one processor.
> So far I've turned off Hyperthreading, set the CpuAffinityMask = 2

Don't play with CPUAffinity, you will end up making the problem worse.
Leave it at the default.

> tried to use gfix to increase the cache buffers(Not sure if that

As long as you don't cause it to need to page to disk (1GB is small
these days)

> Is there anything else I can do? Is it worth me upgrading to FB
> 1.5.4? Or even 2.0.1?

1.5.4, definately (but not for performance reasons, it is a
maintenance release for bugs etc). 2.0.1 should generally give better
performance both with a better optimiser and smarter garbage
collection, but may be more of an effort if you have bad SQL in some

> Can I log long running queries?

Not at the moment, unless you can do some client side profiling. It is
in the roadmap.

> Are there any other settings that might help?

Running classic server will allow it to use both CPUs. It uses more
resources than Superserver, but if something is hogging the CPU, other
queries have a better chance. You can also see when a single
connection is hogging the CPU, and if you are able to systematically
shutdown applications or services you may find a culprit, or at least
a point to investigate from.

If your problem is garbage related, then a temporary fix might be to
(with no-one else connected) run a backup using gbak and the -g
switch, then restore that backup.