Re: type cache cleanup improvements

Noah Misch <noah@leadboat.com>

From: Noah Misch <noah@leadboat.com>

To: Alexander Korotkov <aekorotkov@gmail.com>

Cc: Pavel Borisov <pashkin.elfe@gmail.com>, Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>, Andrei Lepikhov <lepihov@gmail.com>, jian he <jian.universality@gmail.com>, Artur Zakirov <zaartur@gmail.com>, Alexander Lakhin <exclusion@gmail.com>, Teodor Sigaev <teodor@sigaev.ru>, Pgsql Hackers <pgsql-hackers@postgresql.org>, Aleksander Alekseev <aleksander@timescale.com>, Tom Lane <tgl@sss.pgh.pa.us>, Michael Paquier <michael@paquier.xyz>

Date: 2025-04-11T20:32:41Z

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

On Tue, Oct 22, 2024 at 08:33:24PM +0300, Alexander Korotkov wrote:
> On Tue, Oct 22, 2024 at 6:10 PM Pavel Borisov <pashkin.elfe@gmail.com> wrote:
> > On Tue, 22 Oct 2024 at 11:34, Alexander Korotkov <aekorotkov@gmail.com> wrote:
> >> I'm going to push this if no objections.

(This became commit b85a9d0.)

> +	/* Call delete_rel_type_cache() if we actually cleared something */
> +	if (hadTupDescOrOpclass)
> +		delete_rel_type_cache_if_needed(typentry);

I think the intent was to maintain the invariant that a RelIdToTypeIdCacheHash
entry exists if and only if certain kinds of data appear in the TypeCacheHash
entry.  However, TypeCacheOpcCallback() clears TCFLAGS_OPERATOR_FLAGS without
maintaining RelIdToTypeIdCacheHash.  Is it right to do that?