Log Message:
powerdns-recursor: updated to 4.1.12

4.1.12
Improvements
Provide CPU usage statistics per thread (worker & distributor).
Use a bounded load-balancing algo to distribute queries.
Implement a configurable ECS cache limit so responses with an ECS scope more \ 
specific than a certain threshold and a TTL smaller than a specific threshold \ 
are not inserted into the records cache at all.

Bug Fixes
Correctly interpret an empty AXFR response to an IXFR query.