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Re: Re: patch: fix performance problems with repated decomprimation of varlena values in plpgsql

Robert Haas <robertmhaas@gmail.com>

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From: Robert Haas <robertmhaas@gmail.com>
To: Pavel Stehule <pavel.stehule@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>, Noah Misch <noah@leadboat.com>, Kevin Grittner <Kevin.Grittner@wicourts.gov>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2011-01-28T19:09:15Z
Lists: pgsql-hackers 
On Tue, Jan 25, 2011 at 11:29 AM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
> variant a) my first patch - detoast on first usage with avoiding to
> useless detoast checking
> variant b) my first patch - detoast on first usage without avoiding to
> useless detoast checking
>
> time for 1 - about 300 ms, a is bout 1.5% faster than b
> time for 2 - about 30000 ms, a is about 3% faster than b

This makes your approach sound pretty good, but it sounds like we
might need to find a better way to structure the code.

-- 
Robert Haas
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