vec_validate_aligned (h->buckets, nbuckets - 1, CLIB_CACHE_LINE_BYTES);
h->writer_lock = clib_mem_alloc_aligned (CLIB_CACHE_LINE_BYTES,
CLIB_CACHE_LINE_BYTES);
vec_validate_aligned (h->buckets, nbuckets - 1, CLIB_CACHE_LINE_BYTES);
h->writer_lock = clib_mem_alloc_aligned (CLIB_CACHE_LINE_BYTES,
CLIB_CACHE_LINE_BYTES);