Re: More work on SortSupport for text - strcoll() and strxfrm() caching

From: Peter Geoghegan <pg(at)heroku(dot)com>
To: Robert Haas <robertmhaas(at)gmail(dot)com>
Cc: Pg Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: More work on SortSupport for text - strcoll() and strxfrm() caching
Date: 2015-10-09 21:31:50
Message-ID: CAM3SWZQ6W2_iMxhFuST2H5PBSVwKgpgdnT5YokLw=b_zzyVYgw@mail.gmail.com
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On Fri, Oct 9, 2015 at 12:11 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> OK, committed that way.

Just for the record, with the same "cities" table as my original post
to this thread, this query:

select count(distinct(city)) from cities;

Goes from taking about 296ms (once it stabilizes), to about 265ms
(once it stabilizes) following today's commit of just the unsigned
integer comparison patch. I've shaved just over 10% off the duration
of this representative sort-heavy query (against a 9.5 baseline),
which is nice.

--
Peter Geoghegan

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