- In generic_file_write(), only set the page's Referenced bit once,
  when the write touches the start of the page.  This is a
  microoptimisation.


=====================================

--- 2.4.19-pre4/mm/filemap.c~aa-150-read_write_tweaks	Tue Mar 26 23:11:33 2002
+++ 2.4.19-pre4-akpm/mm/filemap.c	Tue Mar 26 23:11:33 2002
@@ -3092,8 +3091,15 @@ generic_file_write(struct file *file,con
 		}
 unlock:
 		kunmap(page);
+
+		/*
+		 * Mark the page accessed if we wrote the
+		 * beginning or we just did an lseek.
+		 */
+		if (!offset || !file->f_reada)
+			SetPageReferenced(page);
+
 		/* Mark it unlocked again and drop the page.. */
-		SetPageReferenced(page);
 		UnlockPage(page);
 		page_cache_release(page);