diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index a67e5181fa900a223c219fa48d33312169a58434..76ade3727cd0ee8dc7364fdae21789c6a26847d0 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -4160,12 +4160,10 @@ ts_ckpt_progress_comparator(Datum a, Datum b, void *arg)
 /*
  * Initialize a writeback context, discarding potential previous state.
  *
- * *max_coalesce is a pointer to a variable containing the current maximum
- * number of writeback requests that will be coalesced into a bigger one. A
- * value <= 0 means that no writeback control will be performed. max_pending
- * is a pointer instead of an immediate value, so the coalesce limits can
- * easily changed by the GUC mechanism, and so calling code does not have to
- * check the current configuration.
+ * *max_pending is a pointer instead of an immediate value, so the coalesce
+ * limits can easily changed by the GUC mechanism, and so calling code does
+ * not have to check the current configuration. A value is 0 means that no
+ * writeback control will be performed.
  */
 void
 WritebackContextInit(WritebackContext *context, int *max_pending)
diff --git a/src/include/storage/buf_internals.h b/src/include/storage/buf_internals.h
index 511d7409e6ef850794aaa09d47faf732daf26000..e0dfb2f5b03b99add82df846f193d28e55d430f8 100644
--- a/src/include/storage/buf_internals.h
+++ b/src/include/storage/buf_internals.h
@@ -300,7 +300,7 @@ extern CkptSortItem *CkptBufferIds;
  * Internal buffer management routines
  */
 /* bufmgr.c */
-extern void WritebackContextInit(WritebackContext *context, int *max_coalesce);
+extern void WritebackContextInit(WritebackContext *context, int *max_pending);
 extern void IssuePendingWritebacks(WritebackContext *context);
 extern void ScheduleBufferTagForWriteback(WritebackContext *context, BufferTag *tag);