Re: PATCH: generate fractional cheapest paths in generate_orderedappend_path

On Thu, Jun 3, 2021 at 1:50 PM Zhihong Yu <zyu(at)yugabyte(dot)com> wrote:

>
>
> On Thu, Jun 3, 2021 at 11:12 AM Tomas Vondra <
> tomas(dot)vondra(at)enterprisedb(dot)com> wrote:
>
>> Hi,
>>
>> On 6/3/21 7:17 PM, Arne Roland wrote:
>> > Hi,
>> >
>> >
>> > I haven't tested the parallel case, but I think we should sort out (3)
>> > get_cheapest_fractional_path_for_pathkeys as mentioned above.
>> >
>>
>> Not sure what you refer to by "above" - it's probably better to reply
>> in-line to existing message, which makes it much cleared.
>>
>> >
>> > I am lost about the comment regarding startup_new_fractional. Could you
>> > elaborate what you mean by that?
>> >
>>
>> Not sure what this refers to either - there's no startup_new_fractional
>> in my message and 'git grep startup_new_fractional' returns nothing.
>>
>> >
>> > Apart from that, I'd argue for a small test case. I attached a slimmed
>> > down case of what we were trying to fix. It might be worth to integrate
>> > that with an existing test, since more than a third of the time seems to
>> > be consumed by the creation and attachment of partitions.
>> >
>>
>> Maybe, if there's a suitable table to reuse, we can do that. But I don't
>> think it matters it takes ~1/3 of the time to attach the partitions.
>> What's more important is whether it measurably slows down the test
>> suite, and I don't think that's an issue.
>>
>> In any case, this seems a bit premature - we need something to test the
>> patch etc. We can worry about how expensive the test is much later.
>>
>> regards
>>
>> --
>> Tomas Vondra
>> EnterpriseDB: http://www.enterprisedb.com
>> The Enterprise PostgreSQL Company
>>
>>
>> Hi,
> In REL_11_STABLE branch, a search revealed the following:
>
> src/backend/optimizer/path/pathkeys.c: *
> get_cheapest_fractional_path_for_pathkeys
> src/backend/optimizer/path/pathkeys.c:get_cheapest_fractional_path_for_pathkeys(List
> *paths,
> src/backend/optimizer/plan/planagg.c:
> get_cheapest_fractional_path_for_pathkeys(final_rel->pathlist,
> src/include/optimizer/paths.h:extern Path
> *get_cheapest_fractional_path_for_pathkeys(List *paths,
>
> It seems this function has been refactored out in subsequent releases.
>
> FYI
>

Sent a bit too soon.

The above function still exists.
But startup_new_fractional was nowhere to be found.