Re: plan time of MASSIVE partitioning ...

Boszormenyi Zoltan írta:
> Boszormenyi Zoltan írta:
>
>> Heikki Linnakangas írta:
>>
>>
>>> On 26.10.2010 18:34, Boszormenyi Zoltan wrote:
>>>
>>>
>>>> thank you very much for pointing me to dynahash, here is the
>>>> next version that finally seems to work.
>>>>
>>>> Two patches are attached, the first is the absolute minimum for
>>>> making it work, this still has the Tree type for canon_pathkeys
>>>> and eq_classes got the same treatment as join_rel_list/join_rel_hash
>>>> has in the current sources: if the list grows larger than 32, a hash
>>>> table
>>>> is created. It seems to be be enough for doing in for
>>>> get_eclass_for_sort_expr()
>>>> only, the other users of eq_classes aren't bothered by this change.
>>>>
>>>>
>>> That's better, but can't you use dynahash for canon_pathkeys as well?
>>>
>>>
>> Here's a purely dynahash solution. It's somewhat slower than
>> the tree version, 0.45 vs 0.41 seconds in the cached case for the
>> previously posted test case.
>>
>>
>
> And now in context diff, sorry for my affection towards unified diffs. :-)
>

A little better version, no need for the heavy hash_any, hash_uint32
on the lower 32 bits on pk_eclass is enough. The profiling runtime
is now 0.42 seconds vs the previous 0.41 seconds for the tree version.

Best regards,
Zoltán Böszörményi

--
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Zoltán Böszörményi
Cybertec Schönig & Schönig GmbH
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