On Tue, Mar 24, 2026 at 11:50 PM Masahiko Sawada <sawada.mshk@gmail.com> wrote: > > > Please find the v3 patch for further review. > > Thank you for updating the patch. I think the patch is reasonably > simple and can avoid unnecessary overheads well due to XID-based > checks. Here are some comments:
Thank you for reviewing the patch.
> vacuum_get_cutoff() is also called by VACUUM FULL, CLUSTER, and > REPACK. I'm not sure that users would expect the slot invalidation > also in these commands. I think it's better to leave > vacuum_get_cutoff() a pure cutoff computation function and we can try > to invalidate slots in heap_vacuum_rel(). It requires additional > ReadNextTransactionId() but we can live with it, or we can make > vacuum_get_cutoffs() return the nextXID as well (stored in *cutoffs).
+1. I chose to perform the slot invalidation in heap_vacuum_rel by getting the next txn ID and calling vacuum_get_cutoffs again when a slot gets invalidated. IMHO, this is simple than adding a flag and do the invalidation selectively in vacuum_get_cutoffs.
> if (TransactionIdPrecedes(oldestXmin, cutoffXID)) > + { > + invalidated = InvalidateObsoleteReplicationSlots(RS_INVAL_XID_AGE, > + 0, > + InvalidOid, > + InvalidTransactionId, > + nextXID); > + } > > I think it's better to check the procArray->replication_slot_xmin and > procArray->replication_slot_catalog_xmin before iterating over each > slot. Otherwise, we would end up checking every slot even when a long > running transaction holds the oldestxmin back.
+1. Changed.
> + if (!TransactionIdIsNormal(cutoffXID)) > + cutoffXID = FirstNormalTransactionId; > > These codes have the same comment but are doing a slightly different > thing. I guess the latter is missing '-'?
Fixed the typo.
I fixed a test error being reported in CI.
Please find the attached v4 patch for further review.
+ if (InvalidateXIDAgedReplicationSlots(vacrel->cutoffs.OldestXmin, + ReadNextTransactionId()))
