The code path in charge of invalidating a replication slot includes a call to pgstat_drop_replslot(), which would result in removing the statistics of the slot once invalidated. However, there is no need to remove the statistics of an invalidated slot as one could still be interested in looking at them to understand the activity of the slot until its actual removal. The initial design of the feature committed in be87200efd used the approach to drop the slots, which is likely why the statistics were still removed during the invalidation. Another problem with this operation is that it was done without holding ReplicationSlotAllocationLock, leaving it unprotected on concurrent activity. This part is arguably a bug, but that's a limited problem in practice so no backpatch is done. In passing, this commit adds a test to check this behavior. The only remaining code path where slot statistics are dropped now related to the slot getting dropped. Author: Bertrand Drouvot Discussion: https://postgr.es/m/ZermH08Eq6YydHpO@ip-10-97-1-34.eu-west-3.compute.internal
PostgreSQL Database Management System
This directory contains the source code distribution of the PostgreSQL database management system.
PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.
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