>>> 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.
Done.
32:06 (with 80MB sort memory)
CPU time was 5:11.
--
Tatsuo Ishii