ceph: reorder fields in 'struct ceph_snapid_map'
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>
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