Re: type cache cleanup improvements

Aleksander Alekseev <aleksander@timescale.com>

From: Aleksander Alekseev <aleksander@timescale.com>

To: Pgsql Hackers <pgsql-hackers@postgresql.org>

Cc: Teodor Sigaev <teodor@sigaev.ru>

Date: 2024-03-05T12:31:45Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Maintain RelIdToTypeIdCacheHash in TypeCacheOpcCallback()
- bb78e4267817 18.0 landed
Fix concurrrently in typcache_rel_type_cache.sql
- aa1e898dea66 18.0 landed
Avoid looping over all type cache entries in TypeCacheRelCallback()
- b85a9d046efd 18.0 landed
- c14d4acb8134 18.0 landed
Update header comment for lookup_type_cache()
- c1500a1ba7e1 18.0 landed
Revert: Avoid looping over all type cache entries in TypeCacheRelCallback()
- 8daa62a10c91 18.0 landed
Introduce hash_search_with_hash_value() function
- d0f020037e19 18.0 landed
Optimize InvalidateAttoptCacheCallback() and TypeCacheTypCallback()
- 40064a8ee1b3 18.0 landed
Refactor initial hash lookup in dynahash.c
- cc5ef90edd80 17.0 landed
Rationalize and improve error messages for some jsonpath items
- 92d2ab7554f9 17.0 cited
Avoid race in RelationBuildDesc() affecting CREATE INDEX CONCURRENTLY.
- fdd965d074d4 15.0 cited
Represent Lists as expansible arrays, not chains of cons-cells.
- 1cff1b95ab6d 13.0 cited

Hi,

> Thank you for interesting in it!
>
> > These changes look very promising. Unfortunately the proposed patches
> > conflict with each other regardless the order of applying:
> >
> > ```
> > error: patch failed: src/backend/utils/cache/typcache.c:356
> > error: src/backend/utils/cache/typcache.c: patch does not apply
> > ```
> Try increase -F option of patch.
>
> Anyway, union of both patches in attachment

Thanks for the quick update.

I tested the patch on an Intel MacBook. A release build was used with
my typical configuration, TWIMC see single-install-meson.sh [1]. The
speedup I got on the provided benchmark is about 150 times. cfbot
seems to be happy with the patch.

I would like to tweak the patch a little bit - change some comments,
add some Asserts, etc. Don't you mind?

[1]: https://github.com/afiskon/pgscripts/

-- 
Best regards,
Aleksander Alekseev