Postgres Pro
Downloads
Home   >   mailing lists

Re: bad estimation together with large work_mem generates terrible slow hash joins - Mailing list pgsql-hackers

From Tomas Vondra
Subject Re: bad estimation together with large work_mem generates terrible slow hash joins
Date
Msg-id 53AC9510.9050201@fuzzy.cz
Whole thread Raw
In response to Re: bad estimation together with large work_mem generates terrible slow hash joins  (Tomas Vondra <tv@fuzzy.cz>)
Responses Re: bad estimation together with large work_mem generates terrible slow hash joins
List pgsql-hackers
Tree view 
On 26.6.2014 20:43, Tomas Vondra wrote:
> Attached is v2 of the patch, with some cleanups / minor improvements:
>
> * there's a single FIXME, related to counting tuples in the

Meh, I couldn't resist resolving this FIXME, so attached is v3 of the
patch. This just adds a proper 'batch tuples' counter to the hash table.

All comments, measurements on different queries etc. welcome. We'll
certainly do a lot of testing, because this was a big issue for us.

regards
Tomas
Attachment

pgsql-hackers by date:

Previous
From: Andres Freund
Date:
Subject: Re: Spinlocks and compiler/memory barriers
Next
From: Tom Lane
Date:
Subject: Re: What's the point of json_extract_path_op etc?