On 7/4/23 13:23, Alvaro Herrera wrote:
> On 2023-Jul-03, Soumyadeep Chakraborty wrote:
>
>> My colleague, Ashwin, pointed out to me that brininsert's per-tuple init
>> of the revmap access struct can have non-trivial overhead.
>>
>> Turns out he is right. We are saving 24 bytes of memory per-call for
>> the access struct, and a bit on buffer/locking overhead, with the
>> attached patch.
>
> Hmm, yeah, I remember being bit bothered by this repeated
> initialization. Your patch looks reasonable to me. I would set
> bistate->bs_rmAccess to NULL in the cleanup callback, just to be sure.
> Also, please add comments atop these two new functions, to explain what
> they are.
>
> Nice results.
>
Yeah. I wonder how much of that runtime is the generate_series(),
though. What's the speedup if that part is subtracted. It's guaranteed
to be even more significant, but by how much?
regards
--
Tomas Vondra
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