Re: queries are fast after dump->restore but slow again after some days dispite vacuum

От: Andrew Dunstan
Тема: Re: queries are fast after dump->restore but slow again after some days dispite vacuum
Дата: ,
Msg-id: 5007FFDD.5050103@dunslane.net
(см: обсуждение, исходный текст)
Ответ на: queries are fast after dump->restore but slow again after some days dispite vacuum  (Felix Scheicher)
Список: pgsql-performance


On 07/19/2012 07:33 AM, Felix Scheicher wrote:
> Hi, I am running a 9.1 server at Ubuntu. When I upgraded to the current version
> I did a pg_dump followed by pg_restore and found that the db was much faster.
> But slowed down again after two days. I did the dump-restore again and could now
> compare the two (actually identical) databases. This is a query of the old one
> directly after a VACUUM ANALYSE:
...
>
> No matter how much I vacuum or analyse the slow db, I don't get it faster.
> I also checked for dead tuples - there are none.


Try running CLUSTER on the relevant tables and see if it makes a
difference. If it does you might want to look into using pg_reorg
periodically.

cheers

andrew


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