user_ns: improve the user_ns on-the-slab packaging

Currently on 64-bit arch the user_namespace is 2096 and when being
kmalloc-ed it resides on a 4k slab wasting 2003 bytes.

If we allocate a separate cache for it and reduce the hash size from 128
to 64 chains the packaging becomes *much* better - the struct is 1072
bytes and the hole between is 98 bytes.

[akpm@linux-foundation.org: s/__initcall/module_init/]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Serge E. Hallyn <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Pavel Emelyanov 2011-01-12 17:00:46 -08:00 committed by Linus Torvalds
parent e020e742e5
commit 6164281ab7
2 changed files with 13 additions and 4 deletions

View file

@ -6,7 +6,7 @@
#include <linux/sched.h>
#include <linux/err.h>
#define UIDHASH_BITS (CONFIG_BASE_SMALL ? 3 : 8)
#define UIDHASH_BITS (CONFIG_BASE_SMALL ? 3 : 7)
#define UIDHASH_SZ (1 << UIDHASH_BITS)
struct user_namespace {