Jorgen Lundman

That is correct - turns out the IO layer in XNU kernels (at least back in 10.8 when we looked at it) can only do two sizes, 512, and 4096...

Run `spindump` when it has gone unresponsive, so we can see all the stacks and where they are

Yeah, it shows its in ``` 2745 zpool_vdev_remove (in libzfs.2.dylib) + 336 [0x10e103068] 2745 zfs_ioctl (in libzfs.2.dylib) + 55 [0x10e110cd5] 2745 ioctl (in libsystem_kernel.dylib) + 151 [0x7fff667ad4eb] 2745 __ioctl (in...

It's ok, you gave really detailed instructions, I'll give it a go in my VM tomorrow.

I have tried your guide - the first problem is that cache devices do not handle /dev/diskX renumbering changes at all, and it was a bit random as to whether...

Strangely - there are no ZFS threads hung in those spindumps.

If `mount_zfs` is not codesigned, it has the same complaints about the libraries. So an unsigned, static, `zfs` binary named `zfs_mount` is the way to go. It does seem to...

OK, takes about 20mins to boot Catalina with 2G of RAM, the spindump during boot looks like: http://www.lundman.net/boot-spindump.txt It seems that any paging falls apart, unsure why yet - if...

With 4GB RAM, it does boot to UI after about 20mins. At which point, I could disable `mds` and `launchctl remove com.apple.appstoreagent`, `zfs set sync=disabled rpool/ROOT/Catalina` to give it a...

And also a spindump waiting long enough for it to be idle. It is still sluggish, and kernel_task is pretty busy - the trick will be to find where. http://www.lundman.net/boot-idle-spindump.txt