Christobol

I forced a power cycle. I rebooted into safe mode, started the array in maintenance mode, and it worked.
-Booted safemode again - Started Array
-System is stuck here like earlier today. I've attached new logs (the prior logs had no updates from what was posted after running ~6 hours other than a reboot command)
-2 cpus are pinned at 100% utilization again
- after ~32 minutes the array started as did one cache pool, the ZFS pool is still mounting -> I do not see a log entry that the other drives were available in the GUI

zpool status -v output


I guess this is a zfs issue? I'll look for next steps. My inclination is to give up on the data on the drive, kill the pool, format and build a new one?

atlas-diagnostics-20250729-1626.zip

Well, the first step was to determine the fragmentation level. As the tool states, the value is mostly meaningless, so unless I found reports of very high fragmentation, there would not be much of a reason to defragment. The thread you linked had a post with the encrypted drive parameter, which answered my original suspicion about why the command I was using wasn't working, my array is encrypted.  
 
For encrypted drives you need to run:
xfs_db -r /dev/mapper/mdXp1         #X is the drive number, and adding /mapper/ is for encrypted arrays in 6.12+
 
So a cheat sheet of commands
-r means read-only
For unRaid 6.12 and newer, non-encrypted arrays use /dev/mdXp1
For unRaid 6.12 and newer, encrypted arrays use /dev/mapper/mdXp1
For unRaid 6.11 and older use /dev/mdX
Not sure if /mapper/ applies to encrypted arrays in 6.11 or older as I cannot test that
 
My drives mostly returned values below 10% total or file fragmentation.  2 drives returned 30%.  With those two am I going to move some files off as they are approaching max capacity anyway.
 
And yes, the xfs_fsr is the defrag command ljm42 used in the thread I posted. I was still in the information-gathering stage.