Thank you for all your replies.

It looks like I should be trying 6.x and recommended that our prospects and customers do too. That is extremely helpful

Regards

Francis

From: Vladimír Čunát <vladimir.cunat@nic.cz>
Sent: Monday, December 29, 2025 7:14 PM
To: Francis Turner <francis@threatstop.com>
Cc: Knot Resolver Users List <knot-resolver-users@lists.nic.cz>
Subject: Re: [knot-resolver-users] Re: Introduction and questions about RPZ support

On 29/12/2025 11.10, Vladimír Čunát via knot-resolver-users wrote:

Also assuming it is supported, what are the performance impacts of large (say 500k+) RPZ policies?

I forgot this part.  In 6.x the main price will be CPU consumed when parsing the file.  (which is asynchronous if you do a reload)  And RAM to hold the resulting database.  We've been quite careful about performance impact on processing DNS requests.