Group some variables based on their sizes to reduce holes.
On x86_64, this shrinks the size of 'struct ceph_snapid_map' from 72 to 64
bytes.
When such a structure is allocated, because of the way memory allocation
works, when 72 bytes were requested, 96 bytes were allocated.
So, on x86_64, this change saves 32 bytes per allocation and has the
structure fit in a single cacheline.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
struct rb_node node;
struct list_head lru;
atomic_t ref;
- u64 snap;
dev_t dev;
+ u64 snap;
unsigned long last_used;
};