Hi Mike, Coly, Kent, As far as I known, ca->heap is used to sort buckets by bucket_prio, and it would be pushed into ca->free_inc queue after sorting. I find ca->heap is double the size of the ca->free_inc. !init_fifo(&ca->free_inc, free << 2, GFP_KERNEL) || !init_heap(&ca->heap, free << 3, GFP_KERNEL) || I am puzzled about, we only need the size of ca->free_inc buckets, Why do we alloc ca->heap the double size of the ca->free_inc? Thanks, Tang Junhui -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html