Comment 10 for bug 1969482

I can also confirm that the fixes in -proposed fixes some severe performance issues on my system, with an encrypted ZFS root filesystem.

It should be noted that if you're using ZFS on an Intel machine with < 4 physical cores, these performance regressions are severe enough to cause the entire machine to noticeably stutter and freeze when the disk is accessed - so this is a fairly serious performance regression for a lot of laptop users!

I think the reason why it's so severe on this configuration is due to ZFS read/write spawning 4 tasks, which have a niceness of -20 causing the userspace to be starved (and perhaps security mitigations stopping/hindering the userspace from using hyperthreading).