Turns out the on-CPU SATA controller isn't available when the NVMe slot is used. 🫢 Swapped SATA ports, no diff. Put the low IOPS disk in a good USB 3 enclosure, hooked to an on-CPU USB controller. Now things are flipped:

                                        capacity     operations     bandwidth 
pool                                  alloc   free   read  write   read  write
------------------------------------  -----  -----  -----  -----  -----  -----
storage-volume-backup                 12.6T  3.74T      0    563      0   293M
  mirror-0                            12.6T  3.74T      0    563      0   293M
    wwn-0x5000c500e8736faf                -      -      0    406      0   146M
    wwn-0x5000c500e8737337                -      -      0    156      0   146M

Interesting. SMART looks pristine on both drives. Brand new drives - Exos X22. Doesn't mean there isn't an impending problem of course. I might try shuffling the links to see if that changes the behaviour on the suggestions of the other comment. Both are currently hooked to an AMD B350 chipset SATA controller. There are two ports that should be hooked to the on-CPU SATA controller. I imagine the two SATA controllers don't share bandwidth. I'll try putting one disk on the on-CPU controller.

Wait, that's a Canadian entity, interesting.

Don't let be called a hypocrite - give $5. 😆

Goddamn.

I'll try 3tsp tomorrow. 👍

I'm dying here. 🤣

And now it no longer shows up.

git merge --no-ff

I was wondering what would be better for discoverability, to write this in a blog post, on GitHub, then link it here, or to just write it here. Turns out Google's crawling Lemmy quite actively. This shows up within the first 10-15 results for "USB DAS ZFS":

It appears that Lemmy is already a good place for writing stuff like this. ☺️

5950X, 64GB

It's a multipurpose machine, desktop workstation, games, running various servers.

I don't know about banning. The text sounds a bit like it's voluntary.