Re: [pgsql-patches] Recalculating OldestXmin in a long-running vacuum

Tom Lane wrote:
> Heikki Linnakangas <heikki(at)enterprisedb(dot)com> writes:
> > I have two runs of DBT-2, one with the patch and one without.
>
> > Patched:
>
> > autovac "public.stock" scans:1 pages:1285990(-0)
> > tuples:25303056(-2671265) CPU 95.22s/38.02u sec elapsed 10351.17 sec
>
> > Unpatched:
>
> > autovac "public.stock" scans:1 pages:1284504(-0)
> > tuples:25001369(-1973760) CPU 86.55s/34.70u sec elapsed 9628.13 sec
>
> So that makes this patch a good idea why? (Maybe what we need to see
> is the impact on the total elapsed time for the DBT-2 test, rather
> than just the VACUUM runtime.)

Yea, in summary, it looks like the patch made the performance worse.

--
Bruce Momjian bruce(at)momjian(dot)us
EnterpriseDB http://www.enterprisedb.com

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