From: Tom Lane <tgl@sss.pgh.pa.us>
To: Qingqing Zhou <zhouqq@cs.toronto.edu>
Cc: pgsql-hackers@postgresql.org
Subject: Re: qsort again (was Re: [PERFORM] Strange Create Index behaviour)
Date: Wed, 15 Feb 2006 23:54:54 -0500
Message-ID: <23297.1140065694@sss.pgh.pa.us> (raw)
In-Reply-To: <dt10bq$1bp$1@news.hub.org>
References: <43F38867.6010701@gpdnet.co.uk>
<19510.1140036968@sss.pgh.pa.us>
<19779.1140038874@sss.pgh.pa.us>
<43F39E53.1020009@gpdnet.co.uk>
<20781.1140046109@sss.pgh.pa.us>
<dt0rn0$2km1$1@news.hub.org>
<23107.1140064820@sss.pgh.pa.us>
<dt10bq$1bp$1@news.hub.org>
"Qingqing Zhou" <zhouqq@cs.toronto.edu> writes:
> "Tom Lane" <tgl@sss.pgh.pa.us> wrote
>> No, I mean I ran the bit of SQL script I gave 100 separate times.
> I must misunderstand something here -- I can't figure out that why the cost
> of the same procedure keep climbing?
No, the run cost varies randomly depending on the random data supplied
by the test script. The reason the numbers are increasing is that I
sorted them for ease of inspection.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, zhouqq@cs.toronto.edu, pgsql-hackers@postgresql.org
Subject: Re: qsort again (was Re: [PERFORM] Strange Create Index behaviour)
In-Reply-To: <23297.1140065694@sss.pgh.pa.us>
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