Hi,
Thank you for the reference to commit 818fefd8fd4 and the related discussion
thread. I understand the intent of introducing initial_restart_lsn was to
preserve a consistent invalidation cause throughout the invalidation loop.
However, I still have a few concerns about this design change:
1. I understand the intention to keep the invalidation cause consistent, but If
a slot's restart_lsn advances significantly during the invalidation
check—indicating it is actively in use—shouldn't we reconsider invalidating it?
2. What potential issues arise if we refrain from invalidating slots whose
restart_lsn advances during the invalidation process? Intuitively, an actively
used slot that has moved it's restart_lsn beyond the problematic point should
not be marked invalid.
3. If the current approach is indeed correct, should we consider making PG15
and earlier consistent with this behavior? The behavioral difference across
versions may lead to different operational outcomes in otherwise similar
situations.
I would appreciate your insights on these points.
Best regards,
suyu.cmj