RRset merge operation is too slow for big RRsets
Query cmts1-dhcp.longlines.com. A
takes more than 10 seconds, probably because some \mathcal{O}(n^2)
complexity in kr_ranked_rrarray_add()
or something like that.
Such query can be used to DoS resolver so we have to fix that.
Edited by Štěpán Balážik