Re: Re: custom hash-based COUNT(DISTINCT) aggregate - unexpectedly high memory consumption - Mailing list pgsql-hackers

From Atri Sharma
Subject Re: Re: custom hash-based COUNT(DISTINCT) aggregate - unexpectedly high memory consumption
Date
Msg-id CAOeZVicivJ6TDdczEyXYaCzwrQN9mtX16JDOsGgbMKu+xR2fFQ@mail.gmail.com
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In response to Re: Re: custom hash-based COUNT(DISTINCT) aggregate - unexpectedly high memory consumption  ("Tomas Vondra" <tv@fuzzy.cz>)
Responses Re: Re: custom hash-based COUNT(DISTINCT) aggregate - unexpectedly high memory consumption
List pgsql-hackers
On Tue, Oct 8, 2013 at 4:15 PM, Tomas Vondra <tv@fuzzy.cz> wrote:
> On 8 Říjen 2013, 11:42, Atri Sharma wrote:
>>>
>>> I've made some significant improvements in the chaining version (in the
>>> master branch), now getting about the memory consumption I've estimated.
>>>
>> I agree, we can hope to reduce the memory consumption by making changes in
>> the current chaining implementation. I would like to look into changing
>> the data structure used for chaining from singly linked list to maybe skip
>> list or something else.
>
> Just to be sure - I haven't been messing with the HashAggregate
> implementation directly, but with a custom aggregate. But feel free to
> tweak the built-in hash table ;-)
>
> Tomas
>

Heh.

Do you mind if I try it out on the custom agg you built? I assume it
is on the github repo link you shared?

Regards,

Atri


--
Regards,

Atri
l'apprenant



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