Thread: pgsql: Avoid looping over all type cache entries in TypeCacheRelCallbac
pgsql: Avoid looping over all type cache entries in TypeCacheRelCallbac
From
Alexander Korotkov
Date:
Avoid looping over all type cache entries in TypeCacheRelCallback() Currently, when a single relcache entry gets invalidated, TypeCacheRelCallback() has to loop over all type cache entries to find appropriate typentry to invalidate. Unfortunately, using the syscache here is impossible, because this callback could be called outside a transaction and this makes impossible catalog lookups. This is why present commit introduces RelIdToTypeIdCacheHash to map relation OID to its composite type OID. We are keeping RelIdToTypeIdCacheHash entry while corresponding type cache entry have something to clean. Therefore, RelIdToTypeIdCacheHash shouldn't get bloat in the case of temporary tables flood. There are many places in lookup_type_cache() where syscache invalidation, user interruption, or even error could occur. In order to handle this, we keep an array of in-progress type cache entries. In the case of lookup_type_cache() interruption this array is processed to keep RelIdToTypeIdCacheHash in a consistent state. Discussion: https://postgr.es/m/5812a6e5-68ae-4d84-9d85-b443176966a1%40sigaev.ru Author: Teodor Sigaev Reviewed-by: Aleksander Alekseev, Tom Lane, Michael Paquier, Roman Zharkov Reviewed-by: Andrei Lepikhov, Pavel Borisov, Jian He, Alexander Lakhin Reviewed-by: Artur Zakirov Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/b85a9d046efdd27775cbe7db9e92aad96aab4ada Modified Files -------------- src/backend/access/transam/xact.c | 10 + src/backend/utils/cache/typcache.c | 359 ++++++++++++++++++--- src/include/utils/typcache.h | 4 + src/test/modules/Makefile | 4 +- src/test/modules/meson.build | 1 + src/test/modules/typcache/.gitignore | 4 + src/test/modules/typcache/Makefile | 28 ++ .../typcache/expected/typcache_rel_type_cache.out | 34 ++ src/test/modules/typcache/meson.build | 16 + .../typcache/sql/typcache_rel_type_cache.sql | 18 ++ src/tools/pgindent/typedefs.list | 1 + 11 files changed, 433 insertions(+), 46 deletions(-)