diff --git a/src/backend/commands/vacuumlazy.c b/src/backend/commands/vacuumlazy.c
index 50085f9a542..95f5952f63f 100644
--- a/src/backend/commands/vacuumlazy.c
+++ b/src/backend/commands/vacuumlazy.c
@@ -104,7 +104,8 @@ typedef struct LVRelStats
 	BlockNumber old_rel_pages;	/* previous value of pg_class.relpages */
 	BlockNumber rel_pages;		/* total number of pages */
 	BlockNumber scanned_pages;	/* number of pages we examined */
-	double		scanned_tuples; /* counts only tuples on scanned pages */
+	BlockNumber	tupcount_pages;	/* pages whose tuples we counted */
+	double		scanned_tuples; /* counts only tuples on tupcount_pages */
 	double		old_rel_tuples; /* previous value of pg_class.reltuples */
 	double		new_rel_tuples; /* new estimated total # of tuples */
 	double		new_dead_tuples;	/* new estimated total # of dead tuples */
@@ -281,6 +282,10 @@ lazy_vacuum_rel(Relation onerel, VacuumStmt *vacstmt,
 	 * density") with nonzero relpages and reltuples=0 (which means "zero
 	 * tuple density") unless there's some actual evidence for the latter.
 	 *
+	 * It's important that we use tupcount_pages and not scanned_pages for the
+	 * check described above; scanned_pages counts pages where we could not get
+	 * cleanup lock, and which were processed only for frozenxid purposes.
+	 *
 	 * We do update relallvisible even in the corner case, since if the table
 	 * is all-visible we'd definitely like to know that.  But clamp the value
 	 * to be not more than what we're setting relpages to.
@@ -290,7 +295,7 @@ lazy_vacuum_rel(Relation onerel, VacuumStmt *vacstmt,
 	 */
 	new_rel_pages = vacrelstats->rel_pages;
 	new_rel_tuples = vacrelstats->new_rel_tuples;
-	if (vacrelstats->scanned_pages == 0 && new_rel_pages > 0)
+	if (vacrelstats->tupcount_pages == 0 && new_rel_pages > 0)
 	{
 		new_rel_pages = vacrelstats->old_rel_pages;
 		new_rel_tuples = vacrelstats->old_rel_tuples;
@@ -455,6 +460,7 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
 	nblocks = RelationGetNumberOfBlocks(onerel);
 	vacrelstats->rel_pages = nblocks;
 	vacrelstats->scanned_pages = 0;
+	vacrelstats->tupcount_pages = 0;
 	vacrelstats->nonempty_pages = 0;
 	vacrelstats->latestRemovedXid = InvalidTransactionId;
 
@@ -645,6 +651,7 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
 		}
 
 		vacrelstats->scanned_pages++;
+		vacrelstats->tupcount_pages++;
 
 		page = BufferGetPage(buf);
 
@@ -1053,7 +1060,7 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
 	/* now we can compute the new value for pg_class.reltuples */
 	vacrelstats->new_rel_tuples = vac_estimate_reltuples(onerel, false,
 														 nblocks,
-												  vacrelstats->scanned_pages,
+												  vacrelstats->tupcount_pages,
 														 num_tuples);
 
 	/*
@@ -1357,7 +1364,7 @@ lazy_cleanup_index(Relation indrel,
 
 	ivinfo.index = indrel;
 	ivinfo.analyze_only = false;
-	ivinfo.estimated_count = (vacrelstats->scanned_pages < vacrelstats->rel_pages);
+	ivinfo.estimated_count = (vacrelstats->tupcount_pages < vacrelstats->rel_pages);
 	ivinfo.message_level = elevel;
 	ivinfo.num_heap_tuples = vacrelstats->new_rel_tuples;
 	ivinfo.strategy = vac_strategy;