Sorry for the less useful rant. Yes, we are integrating with IPA for just uid/gid mappings. From the little time we got to debug before giving up, FreeBSD was fast and working as usual before IPA client enrolment was done. We tried NFSv3 (with separate lockd) and NFSv4.2 both only performing at about 20% the throughput of what we currently get out of ZFS on Linux. Both ZFS versions being the same. ZFS-2.1

It felt like we were in uncharted waters with the IPA client and gave up instead of fixing the problems.

I wish there was Pkg install ipa-client