Hello, In this other use-case, described in the thread "IXFR commit time scaling", there was a reply refering to https://www.knot-dns.cz/docs/3.5/singlehtml/#signing-threads and https://www.knot-dns.cz/docs/3.5/singlehtml/#adjust-threads Which made me wonder... a] you can have an external networked HSM, which sounds promising to speed up signing a lot... b] nowadays you also have even 128 core processers, even mutiple CPU slots, which sounds as a immense boost for co-proccesing... c] you could combine those... Clinical data would propably be hard, but hypothetical/esitimated; what would be wise/pointless/smart/insane to increase signing of large zones? I'd expect that RAM speed is a major factor also. What would be an ideal setup today? -- With kind regards, Met vriendelijke groet, Mit freundlichen Grüß, Leo Vandewoestijne &lt;***(a)dns.company&gt; <www.dns.company>