> 6 сент. 2020 г., в 18:26, Heikki Linnakangas <hlinnaka@iki.fi> написал(а):
>
> On 05/09/2020 14:53, Andrey M. Borodin wrote:
>> Thanks for ideas, Heikki. Please see v13 with proposed changes.
>
> Thanks, that was quick!
>
>> But I've found out that logging page-by-page slows down GiST build by
>> approximately 15% (when CPU constrained). Though In think that this
>> is IO-wise.
> Hmm, any ideas why that is? log_newpage_range() writes one WAL record for 32 pages, while now you're writing one
recordper page, so you'll have a little bit more overhead from that. But 15% seems like a lot.
Hmm, this works for B-tree too.
this index creation
psql -c '\timing' -c "create table x as select random() from generate_series(1,10000000,1);" -c "create index ON x
(random);"
takes 7 seconds on may machine, but with one weird patch it takes only 6 :)
Maybe I'm missing something? Like forgot to log 10% of pages, or something like that...
Best regards, Andrey Borodin.
