Re: Tsearch2 Initial Search Speed
От | Howard Cole |
---|---|
Тема | Re: Tsearch2 Initial Search Speed |
Дата | |
Msg-id | 485789C1.3000803@selestial.com обсуждение исходный текст |
Ответ на | Re: Tsearch2 Initial Search Speed (Alan Hodgson <ahodgson@simkin.ca>) |
Ответы |
Re: Tsearch2 Initial Search Speed
Re: Tsearch2 Initial Search Speed |
Список | pgsql-performance |
Alan Hodgson wrote: > It's because everything is cached, in particular the relevant rows from > the "email" table (accessing which took 22 of the original 27 seconds). > > The plan looks good for what it's doing. > > I don't see that query getting much faster unless you could add a lot more > cache RAM; 30K random IOs off disk is going to take a fair bit of time > regardless of what you do. > > Thanks Alan, I guessed that the caching was the difference, but I do not understand why there is a heap scan on the email table? The query seems to use the email_fts_index correctly, which only takes 6 seconds, why does it then need to scan the email table? Sorry If I sound a bit stupid - I am not very experienced with the analyse statement.
В списке pgsql-performance по дате отправления: