mirror of
https://github.com/neondatabase/neon.git
synced 2026-01-15 17:32:56 +00:00
ea7be4152a
## Problem In staging, we could see that occasionally tenants were wrapping their pageserver_visible_physical_size metric past zero to 2^64. This is harmless right now, but will matter more later when we start using visible size in things like the /utilization endpoint. ## Summary of changes - Add debug asserts that detect this case. `test_gc_of_remote_layers` works as a reproducer for this issue once the asserts are added. - Tighten up the interface around access_stats so that only Layer can mutate it. - In Layer, wrap calls to `record_access` in code that will update the visible size statistic if the access implicitly marks the layer visible (this was what caused the bug) - In LayerManager::rewrite_layers, use the proper set_visibility layer function instead of directly using access_stats (this is an additional path where metrics could go bad.) - Removed unused instances of LayerAccessStats in DeltaLayer and ImageLayer which I noticed while reviewing the code paths that call record_access.