diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index 1adb6d3..310cd95 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -654,6 +654,10 @@ BufferAlloc(SMgrRelation smgr, char relpersistence, ForkNumber forkNum,
 				FlushBuffer(buf, NULL);
 				LWLockRelease(buf->content_lock);
 
+				/* The bgwriter may need to be woken. */
+				if (ProcGlobal->bgwriterLatch)
+					SetLatch(ProcGlobal->bgwriterLatch);
+
 				TRACE_POSTGRESQL_BUFFER_WRITE_DIRTY_DONE(forkNum, blockNum,
 											   smgr->smgr_rnode.node.spcNode,
 												smgr->smgr_rnode.node.dbNode,
@@ -2368,9 +2372,6 @@ SetBufferCommitInfoNeedsSave(Buffer buffer)
 			VacuumPageDirty++;
 			if (VacuumCostActive)
 				VacuumCostBalance += VacuumCostPageDirty;
-			/* The bgwriter may need to be woken. */
-			if (ProcGlobal->bgwriterLatch)
-				SetLatch(ProcGlobal->bgwriterLatch);
 		}
 	}
 }