v10-0010-Keep-all_frozen-updated-too-in-heap_page_prune_a.patch

From 3ac96aa83bad6be7347b5103fb8b31d42c975f2d Mon Sep 17 00:00:00 2001
From: Melanie Plageman <melanieplageman@gmail.com>
Date: Wed, 23 Jul 2025 16:01:24 -0400
Subject: [PATCH v10 10/22] Keep all_frozen updated too in
 heap_page_prune_and_freeze

We previously relied on only using all-visible and all-frozen together
but it's best to keep them both updated.

Future commits will separate usage of these fields, so it is best not to
rely on all_visible for all_frozen's validity.
---
 src/backend/access/heap/pruneheap.c | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/src/backend/access/heap/pruneheap.c b/src/backend/access/heap/pruneheap.c
index e0005c2d4f2..10d030fb3e7 100644
--- a/src/backend/access/heap/pruneheap.c
+++ b/src/backend/access/heap/pruneheap.c
@@ -143,10 +143,6 @@ typedef struct
 	 * whether to freeze the page or not.  The all_visible and all_frozen
 	 * values returned to the caller are adjusted to include LP_DEAD items at
 	 * the end.
-	 *
-	 * all_frozen should only be considered valid if all_visible is also set;
-	 * we don't bother to clear the all_frozen flag every time we clear the
-	 * all_visible flag.
 	 */
 	bool		all_visible;
 	bool		all_frozen;
@@ -828,6 +824,7 @@ heap_page_prune_and_freeze(Relation relation, Buffer buffer,
 		 */
 	}
 
+	Assert(!prstate.all_frozen || prstate.all_visible);
 	/* Any error while applying the changes is critical */
 	START_CRIT_SECTION();
 
@@ -1472,7 +1469,7 @@ heap_prune_record_unchanged_lp_normal(Page page, PruneState *prstate, OffsetNumb
 
 				if (!HeapTupleHeaderXminCommitted(htup))
 				{
-					prstate->all_visible = false;
+					prstate->all_visible = prstate->all_frozen = false;
 					break;
 				}
 
@@ -1494,7 +1491,7 @@ heap_prune_record_unchanged_lp_normal(Page page, PruneState *prstate, OffsetNumb
 				Assert(prstate->cutoffs);
 				if (!TransactionIdPrecedes(xmin, prstate->cutoffs->OldestXmin))
 				{
-					prstate->all_visible = false;
+					prstate->all_visible = prstate->all_frozen = false;
 					break;
 				}
 
@@ -1507,7 +1504,7 @@ heap_prune_record_unchanged_lp_normal(Page page, PruneState *prstate, OffsetNumb
 
 		case HEAPTUPLE_RECENTLY_DEAD:
 			prstate->recently_dead_tuples++;
-			prstate->all_visible = false;
+			prstate->all_visible = prstate->all_frozen = false;
 
 			/*
 			 * This tuple will soon become DEAD.  Update the hint field so
@@ -1526,7 +1523,7 @@ heap_prune_record_unchanged_lp_normal(Page page, PruneState *prstate, OffsetNumb
 			 * assumption is a bit shaky, but it is what acquire_sample_rows()
 			 * does, so be consistent.
 			 */
-			prstate->all_visible = false;
+			prstate->all_visible = prstate->all_frozen = false;
 
 			/*
 			 * If we wanted to optimize for aborts, we might consider marking
@@ -1544,7 +1541,7 @@ heap_prune_record_unchanged_lp_normal(Page page, PruneState *prstate, OffsetNumb
 			 * will commit and update the counters after we report.
 			 */
 			prstate->live_tuples++;
-			prstate->all_visible = false;
+			prstate->all_visible = prstate->all_frozen = false;
 
 			/*
 			 * This tuple may soon become DEAD.  Update the hint field so that
-- 
2.43.0