Re: Better tracking of free space during SP-GiST index build

On 09/25/2016 08:33 PM, Oleg Bartunov wrote:
> On Sat, Sep 24, 2016 at 11:32 PM, Tomas Vondra
> <tomas(dot)vondra(at)2ndquadrant(dot)com> wrote:
>> On 09/22/2016 07:37 PM, Tom Lane wrote:
>>>
>>> Tomas Vondra <tomas(dot)vondra(at)2ndquadrant(dot)com> writes:
>>>
>>>> ... I've tried increasing the cache size to 768
>>>> entries, with vast majority of them (~600) allocated to leaf pages.
>>>> Sadly, this seems to only increase the CREATE INDEX duration a bit,
>>>> without making the index significantly smaller (still ~120MB).
>>>
>>>
>>> Yeah, that's in line with my results: not much further gain from a
>>> larger cache. Though if you were testing with the same IRRExplorer
>>> data, it's not surprising that our results would match. Would be
>>> good to try some other cases...
>>>
>>
>> Agreed, but I don't have any other data sets at hand. One possibility would
>> be to generate something randomly (e.g. it's not particularly difficult to
>> generate random IP addresses), but I'd much rather use some real-world data
>> sets.
>
> Tomas, I have one real dataset, which I used for testing spgist
> (https://www.postgresql.org/message-id/CAF4Au4zxd2XOV0A__FU7xoHxSiwJzm1z2xhs-FFaT1DzB9ub3Q@mail.gmail.com)
> Let me know if you need it.
>

Sure, that would be useful.

I think it would be useful to make repository of such data sets, so that
patch authors & reviewers can get a reasonable collection of data sets
if needed, instead of scrambling every time. Opinions?

regards

--
Tomas Vondra http://www.2ndQuadrant.com
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