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

From: Tomas Vondra <tv(at)fuzzy(dot)cz>
To: pgsql-hackers(at)postgresql(dot)org
Subject: Re: bad estimation together with large work_mem generates terrible slow hash joins
Date: 2014-09-12 21:09:03
Message-ID: 541360EF.7030207@fuzzy.cz
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On 12.9.2014 22:24, Robert Haas wrote:
> On Fri, Sep 12, 2014 at 3:39 PM, Tomas Vondra <tv(at)fuzzy(dot)cz> wrote:
>>
>> Yes, I like those changes and I think your reasoning is correct in both
>> cases. It certainly makes the method shorter and more readable - I was
>> too "stuck" in the original logic, so thanks for improving this.
>>
>> So +1 from me to those changes.
>
> OK, committed. Please rebase the rest.

Attached is v15 of the patch, rebased to current HEAD.

Tomas

Attachment Content-Type Size
hashjoin-nbuckets-v15-resize.patch text/x-diff 10.3 KB

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