InnoDB Testing, Discussion Results

Bradley Baetz bbaetz at
Tue Aug 8 13:33:25 UTC 2006

On 08/08/06, Max Kanat-Alexander <mkanat at> wrote:
>         Looking into it (using MySQL's slow query log), I did find that under
> high numbers of simultaneous users, certain buglist searches do spend a
> lot of time waiting for WRITE locks on the database to release. That is,
> every time somebody uses process_bug or post_bug, it's going to slow
> down queries. If we were under transactions, this would end.

We shouldn't have WRITE locks for any period of time. If you're not
doing replication, what you'll find is that readers block writers - ie
you're waiting for WRITE locks, because someone else has a read log.

You may want to test that - it will improve, but you'll still have row
level exclusive locks (yes, its more complicated than that, but for
our purposes...)


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