Count buffers dirtied due to hints in pgBufferUsage.shared_blks_dirtied.

Previously, such buffers weren't counted, with the possible result that
EXPLAIN (BUFFERS) and pg_stat_statements would understate the true
number of blocks dirtied by an SQL statement.

Back-patch to 9.2, where this counter was introduced.

Amit Kapila

diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index a5e97c761da45e69d32473771608a027679fcf7b..f2f42659c14ace3e78893b85f496f15f71fddee5 100644 (file)
--- 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;
        }