Re: bad estimation together with large work_mem generates terrible slow hash joins

Поиск
Список
Период
Сортировка
От Tomas Vondra
Тема Re: bad estimation together with large work_mem generates terrible slow hash joins
Дата
Msg-id 53CBEE6E.8080702@fuzzy.cz
обсуждение исходный текст
Ответ на Re: bad estimation together with large work_mem generates terrible slow hash joins  (Tomas Vondra <tv@fuzzy.cz>)
Ответы Re: bad estimation together with large work_mem generates terrible slow hash joins  (Tomas Vondra <tv@fuzzy.cz>)
Список pgsql-hackers
Attached v9 of the patch. Aside from a few minor fixes, the main  change
is that this is assumed to be combined with the "dense allocation" patch.

It also rewrites the ExecHashIncreaseNumBuckets to follow the same
pattern as ExecHashIncreaseNumBatches (i.e. scanning chunks directly,
instead of buckets). It's cleaner and more consistent.

hashjoin-nbuckets-growth-v9.patch contains only this patch, so you need
to grab the hashjoin-alloc-v4.patch from a different thread and apply it
first)

hashjoin-nbuckets-growth-v9-combined.patch contains both patches combined

regards
Tomas Vondra

Вложения

В списке pgsql-hackers по дате отправления:

Предыдущее
От: Tomas Vondra
Дата:
Сообщение: Re: tweaking NTUP_PER_BUCKET
Следующее
От: Martijn van Oosterhout
Дата:
Сообщение: Re: SQL MERGE is quite distinct from UPSERT