From 36d1fa2a89b3fb354a813354496df475ee11b62e Mon Sep 17 00:00:00 2001 From: Alexey Kondratov Date: Tue, 24 Dec 2019 18:21:50 +0300 Subject: [PATCH v1] Make phsycal replslot advance persistent --- src/backend/replication/slotfuncs.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/src/backend/replication/slotfuncs.c b/src/backend/replication/slotfuncs.c index 46e6dd4d12..826708d3f6 100644 --- a/src/backend/replication/slotfuncs.c +++ b/src/backend/replication/slotfuncs.c @@ -358,12 +358,14 @@ pg_get_replication_slots(PG_FUNCTION_ARGS) * The LSN position to move to is compared simply to the slot's restart_lsn, * knowing that any position older than that would be removed by successive * checkpoints. + * + * Returns InvalidXLogRecPtr if no-op. */ static XLogRecPtr pg_physical_replication_slot_advance(XLogRecPtr moveto) { XLogRecPtr startlsn = MyReplicationSlot->data.restart_lsn; - XLogRecPtr retlsn = startlsn; + XLogRecPtr retlsn = InvalidXLogRecPtr; if (startlsn < moveto) { @@ -386,6 +388,8 @@ pg_physical_replication_slot_advance(XLogRecPtr moveto) * because we need to digest WAL to advance restart_lsn allowing to recycle * WAL and removal of old catalog tuples. As decoding is done in fast_forward * mode, no changes are generated anyway. + * + * Returns InvalidXLogRecPtr if no-op. */ static XLogRecPtr pg_logical_replication_slot_advance(XLogRecPtr moveto) @@ -393,7 +397,7 @@ pg_logical_replication_slot_advance(XLogRecPtr moveto) LogicalDecodingContext *ctx; ResourceOwner old_resowner = CurrentResourceOwner; XLogRecPtr startlsn; - XLogRecPtr retlsn; + XLogRecPtr retlsn = InvalidXLogRecPtr; PG_TRY(); { @@ -414,9 +418,6 @@ pg_logical_replication_slot_advance(XLogRecPtr moveto) */ startlsn = MyReplicationSlot->data.restart_lsn; - /* Initialize our return value in case we don't do anything */ - retlsn = MyReplicationSlot->data.confirmed_flush; - /* invalidate non-timetravel entries */ InvalidateSystemCaches(); @@ -480,9 +481,9 @@ pg_logical_replication_slot_advance(XLogRecPtr moveto) * better than always losing the position even on clean restart. */ ReplicationSlotMarkDirty(); - } - retlsn = MyReplicationSlot->data.confirmed_flush; + retlsn = MyReplicationSlot->data.confirmed_flush; + } /* free context, call shutdown callback */ FreeDecodingContext(ctx); @@ -575,7 +576,7 @@ pg_replication_slot_advance(PG_FUNCTION_ARGS) nulls[0] = false; /* Update the on disk state when lsn was updated. */ - if (XLogRecPtrIsInvalid(endlsn)) + if (!XLogRecPtrIsInvalid(endlsn)) { ReplicationSlotMarkDirty(); ReplicationSlotsComputeRequiredXmin(false); -- 2.17.1