Re: [HACKERS] sort on huge table - Mailing list pgsql-hackers

From Tatsuo Ishii
Subject Re: [HACKERS] sort on huge table
Date
Msg-id 199911010635.PAA26145@srapc451.sra.co.jp
Whole thread Raw
In response to Re: [HACKERS] sort on huge table  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: [HACKERS] sort on huge table  (Tatsuo Ishii <t-ishii@sra.co.jp>)
List pgsql-hackers
>Tatsuo Ishii <t-ishii@sra.co.jp> writes:
>> It worked with 2GB+ table but was much slower than before.
>> Before(with 8MB sort memory): 22 minutes
>> After(with 8MB sort memory): 1 hour and 5 minutes
>> After(with 80MB sort memory): 42 minutes.
>
>I've committed some changes to tuplesort.c to try to improve
>performance.  Would you try your test case again with current
>sources?  Also, please see if you can record the CPU time
>consumed by the backend while doing the sort.

It's getting better, but still slower than before.

52:50 (with 8MB sort memory)

ps shows 7:15 was consumed by the backend. I'm going to test with 80MB 
sort memory.
--
Tatsuo Ishii


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