nfsd41: reserve less memory for DRC

Also remove a slightly misleading comment.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

fs/nfsd/nfssvc.c

@@ -246,8 +246,7 @@ void nfsd_reset_versions(void)
  */
 static void set_max_drc(void)
 {
-	/* The percent of nr_free_buffer_pages used by the V4.1 server DRC */
-	#define NFSD_DRC_SIZE_SHIFT	7
+	#define NFSD_DRC_SIZE_SHIFT	10
 	nfsd_drc_max_pages = nr_free_buffer_pages()
 						>> NFSD_DRC_SIZE_SHIFT;
 	nfsd_drc_pages_used = 0;