diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index a5e97c761da..f2f42659c14 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -2708,6 +2708,7 @@ MarkBufferDirtyHint(Buffer buffer, bool buffer_std)
 		if (dirtied)
 		{
 			VacuumPageDirty++;
+			pgBufferUsage.shared_blks_dirtied++;
 			if (VacuumCostActive)
 				VacuumCostBalance += VacuumCostPageDirty;
 		}