From: Nick Piggin <npiggin@suse.de>

Reduce radix tree node memory usage by about a factor of 4 for small files
(< 64K).  There are pointer traversal and memory usage costs for large
files with dense pagecache.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 lib/radix-tree.c |    2 +-
 1 files changed, 1 insertion(+), 1 deletion(-)

diff -puN lib/radix-tree.c~radix-tree-small lib/radix-tree.c
--- devel/lib/radix-tree.c~radix-tree-small	2006-04-24 21:59:34.000000000 -0700
+++ devel-akpm/lib/radix-tree.c	2006-04-24 21:59:34.000000000 -0700
@@ -33,7 +33,7 @@
 
 
 #ifdef __KERNEL__
-#define RADIX_TREE_MAP_SHIFT	6
+#define RADIX_TREE_MAP_SHIFT	(CONFIG_BASE_SMALL ? 4 : 6)
 #else
 #define RADIX_TREE_MAP_SHIFT	3	/* For more stressful testing */
 #endif
_