Re: I: About "Our CLUSTER implementation is pessimal" patch

On Wed, Sep 29, 2010 at 1:12 AM, Itagaki Takahiro
<itagaki(dot)takahiro(at)gmail(dot)com> wrote:
> On Wed, Sep 29, 2010 at 1:27 PM, Alvaro Herrera
> <alvherre(at)commandprompt(dot)com> wrote:
>>> I see a consistent
>>> ~10% advantage for the sequential scan clusters.
>>
>> 10% is nothing.  I was expecting this patch would give an order of
>> magnitude of improvement or somethine like that in the worst cases of
>> the current code (highly unsorted input)
>
> Yes. It should be x10 faster than ordinary method in the worst cases.
>
> I have a performance result of pg_reorg, that performs as same as
> the patch. It shows 16 times faster than the old CLUSTER. In addition,
> it was slow if not fragmented. (So, it should not be "consistent".)
> http://reorg.projects.postgresql.org/

Can you reproduce that with this patch?

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Robert Haas
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