If you are on 22.05 and experiencing high CPU usage, see this post for a fix

[drewsaur]

https://forum.netgate.com/topic/172770/22-05-rc-high-cpu-load/20?_=1656773452211

It references this fix to pfBlockerNG posted by @BBcan177 :

tl;dr - use Diagnostics > Command Prompt to load and edit line 4139 of /usr/local/pkg/pfblockerng/pfblockerng.inc from

$r = explode(')', $result, 2);

To:

$r = explode(' ', $result, 2);

Save the file and restart the pfb_filter Service for the changes to take effect.