Hi, Daniil Davydov.
Thanks for sharing your patch!
It was quite a while since I last looked at the patch. I've tested it again,
and still get regression on patched version where a table has many columns.
And it is totally CPU-bounded on tts_virtual_copyslot.
Unpatched version:
1 col:
Time: 8909.714 ms (00:08.910)
Time: 8803.579 ms (00:08.804)
Time: 8600.415 ms (00:08.600)
32 cols:
Time: 12911.699 ms (00:12.912)
Time: 13543.491 ms (00:13.543)
Time: 13325.368 ms (00:13.325)
Patched version:
1 col:
Time: 3532.841 ms (00:03.533)
Time: 3598.223 ms (00:03.598)
Time: 3515.858 ms (00:03.516)
32 cols:
Time: 35647.724 ms (00:35.648)
Time: 35596.233 ms (00:35.596)
Time: 35669.106 ms (00:35.669)
I've tested your patch with tuplestore and found the regression does not exist
anymore, but I haven't look deep inside it.
Patched version (with tuplestore):
1 col:
Time: 3500.502 ms (00:03.501)
Time: 3486.886 ms (00:03.487)
Time: 3514.233 ms (00:03.514)
32 cols:
Time: 10375.391 ms (00:10.375)
Time: 10248.256 ms (00:10.248)
Time: 10248.289 ms (00:10.248)
It seems to be a good idea if there is no other issue with your patch.
--
Regards,
Jingtang
