Re: Speed up transaction completion faster after many relations are accessed in a transaction

On Mon, 17 Jun 2019 at 15:05, Tsunakawa, Takayuki
<tsunakawa(dot)takay(at)jp(dot)fujitsu(dot)com> wrote:
> (1)
> +#define LOCKMETHODLOCALHASH_SHRINK_SIZE 64
>
> How about LOCKMETHODLOCALHASH_SHRINK_THRESHOLD, because this determines the threshold value to trigger shrinkage? Code in PostgreSQL seems to use the term threshold.

That's probably better. I've renamed it to that.

> (2)
> +/* Complain if the above are not set to something sane */
> +#if LOCKMETHODLOCALHASH_SHRINK_SIZE < LOCKMETHODLOCALHASH_INIT_SIZE
> +#error "invalid LOCKMETHODLOCALHASH_SHRINK_SIZE"
> +#endif
>
> I don't think these are necessary, because these are fixed and not configurable. FYI, src/include/utils/memutils.h doesn't have #error to test these macros.

Yeah. I was thinking it was overkill when I wrote it, but somehow
couldn't bring myself to remove it. Done now.

> (3)
> + if (hash_get_num_entries(LockMethodLocalHash) == 0 &&
> + hash_get_max_bucket(LockMethodLocalHash) >
> + LOCKMETHODLOCALHASH_SHRINK_SIZE)
> + CreateLocalLockHash();
>
> I get an impression that Create just creates something where there's nothing. How about Init or Recreate?

Renamed to InitLocalLoclHash()

v5 is attached.

Thank you for the review.

--
David Rowley http://www.2ndQuadrant.com/
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