Re: calling procedures is slow and consumes extra much memory against calling function

On Sat, 16 May 2020 at 00:07, Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com> wrote:
>
> Hi
>
>>>
>>> The problem is in plpgsql implementation of CALL statement
>>>
>>> In non atomic case - case of using procedures from DO block, the expression plan is not cached, and plan is generating any time. This is reason why it is slow.
>>>
>>> Unfortunately, generated plans are not released until SPI_finish. Attached patch fixed this issue.
>>
>>
>> But now, recursive calling doesn't work :-(. So this patch is not enough
>
>
> Attached patch is working - all tests passed

Could you show an example testcase that tests this recursive scenario,
with which your earlier patch fails the test, and this v2 patch passes
it ? I am trying to understand the recursive scenario and the re-use
of expr->plan.

>
> It doesn't solve performance, and doesn't solve all memory problems, but significantly reduce memory requirements from 5007 bytes to 439 bytes per one CALL

So now this patch's intention is to reduce memory consumption, and it
doesn't target slowness improvement, right ?

--
Thanks,
-Amit Khandekar
Huawei Technologies