Previously, the size of struct kmem_cache was 136 bytes, just eight bytes larger than 128 bytes, which is typically two cache lines on today's CPUs.
By reducing the size of the name field which holds a human-readable description by eight bytes to 24 bytes, the struct kmem_cache can be made fit into two cache lines. This change should not affect the usefulness of this field. For reference, the length of the largest hard-coded name is 17. * kern/slab.h (KMEM_CACHE_NAME_SIZE): Define to 24. --- kern/slab.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kern/slab.h b/kern/slab.h index b842fb7..a4219c4 100644 --- a/kern/slab.h +++ b/kern/slab.h @@ -149,7 +149,7 @@ typedef void (*kmem_slab_free_fn_t)(vm_offset_t, vm_size_t); /* * Cache name buffer size. */ -#define KMEM_CACHE_NAME_SIZE 32 +#define KMEM_CACHE_NAME_SIZE 24 /* * Cache of objects. -- 1.8.5.2
