Re: JIT compilation per plan node

On 2/20/24 06:38, David Rowley wrote:
> On Tue, 20 Feb 2024 at 18:31, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> FWIW, I seriously doubt that an extra walk of the plan tree is even
>> measurable compared to the number of cycles JIT compilation will
>> expend if it's called. So I don't buy your argument here.
>> We would be better off to do this in a way that's clean and doesn't
>> add overhead for non-JIT-enabled builds.
>
> The extra walk of the tree would need to be done for every plan, not
> just the ones where we do JIT. I'd rather find a way to not add this
> extra plan tree walk, especially since the vast majority of cases on
> an average instance won't be doing any JIT.
>

I believe Tom was talking about non-JIT-enabled-builds, i.e. builds that
either don't support JIT at all, or where jit=off. Those would certainly
not need the extra walk.

regards

--
Tomas Vondra
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