InnoDB Testing, Discussion Results

[Benton, Kevin]

> On 08/08/06, Max Kanat-Alexander <mkanat at bugzilla.org> 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...)

If we do this, we have to be especially careful to make sure we release
locks explicitly using mod_perl.

---
Kevin Benton
Perl/Bugzilla Developer/Administrator, Perforce SCM Administrator
AMD - ECSD Software Validation and Tools
 
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