Horton

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

Pavel Stehule <pavel.stehule@gmail.com>

View thread
From: Pavel Stehule <pavel.stehule@gmail.com>
To: Robert Haas <robertmhaas@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: 2011-01-28T19:19:36Z
Lists: pgsql-hackers 
2011/1/28 Robert Haas <robertmhaas@gmail.com>:
> 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.
>

do you have a any idea?

Pavel

> --
> Robert Haas
> EnterpriseDB: http://www.enterprisedb.com
> The Enterprise PostgreSQL Company
>