Re: opportunistic tuple freezing

On Mon, Sep 14, 2009 at 2:07 AM, Jeff Davis <pgsql(at)j-davis(dot)com> wrote:

> On Mon, 2009-08-17 at 10:22 -0400, Tom Lane wrote:
> > As always with patches that are meant to improve performance,
> > some experimental evidence would be a good thing.
>
> I haven't had time to performance test this patch yet, and it looks like
> it will take a significant amount of effort to do so. I'm focusing on my
> other work, so I don't know if this one is going to be in shape for the
> September commitfest.
>
> If someone is interested in doing some performance testing for this
> patch, let me know. I still think it has potential.
>
>
Does the community think that experimental performance testing is a
must-have in order for this patch to be acceptable? If so, it sounds like
this should be marked as rejected or RwF, and no longer considered for this
commit fest, and I should move on to a different patch.

I'll do some work on benchmarking it, but since it takes hundreds of
millions of transactions to make a plausible scenario, this will not be done
any time soon.

Also, I see that the number of frozen tuples is not logged. I'd like to add
that to the info reported under Log_autovacuum_min_duration, both to help
evaluate this patch and because it seems like something that should be
reported.

Cheers,

Jeff Janes