Re: hashagg slowdown due to spill changes - Mailing list pgsql-hackers

From Jeff Davis
Subject Re: hashagg slowdown due to spill changes
Date
Msg-id 9d786d5d77c404834c033c0710f4f6d0c7702bb1.camel@j-davis.com
Whole thread Raw
In response to Re: hashagg slowdown due to spill changes  (Peter Geoghegan <pg@bowt.ie>)
Responses Re: hashagg slowdown due to spill changes  (Peter Geoghegan <pg@bowt.ie>)
List pgsql-hackers
On Sat, 2020-07-25 at 15:08 -0700, Peter Geoghegan wrote:
> I find that Andres original "SELECT cat, count(*) FROM
> fewgroups_many_rows GROUP BY 1;" test case is noticeably improved by
> the patch. Without the patch, v13 takes ~11.46 seconds. With the
> patch, it takes only ~10.64 seconds.

I saw less of an improvement than you or Andres (perhaps just more
noise). But given that both you and Andres are reporting a measurable
improvement, then I went ahead and committed it. Thank you.

Regards,
    Jeff Davis





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