[dnsdist] dnsdist 1.7.4 Debian Bullseye vs 1.8.4 Bullseye

[Aleš Rygl]

Hello,

     I would to kindly ask for help or and advice. I have just upgraded 
one of our dnsdist instances from 1.7.4 do 1.8.4 together with OS 
upgrade (Debian 11.7 to 12.1). Everything works fine, no issues observed 
apart some deprecated config references. What is a big surprise to me is 
CPU usage. The newer version has nearly two times higher CPU consumption 
in userspace. I am nearly at 80% CPU with 16 physical cores (was about 
40%). We have a lot of TLS (DoT) sessions (30k) and 60kqps in total (30k 
via DoT) here. The latency measured by dnsdist went up also. We are 
collecting all the metrics dnsdist produces via graphite so I can check 
counters, what could be wrong.

     Thanks in advance

With best regards

Ales