I see that in your tests Octopus delivers more than twice iops with 1 OSD.
Can I ask you what's my problem then? :-)
I have a 4-node Ceph cluster with 14 NVMe drives and fast CPUs (Threadrippers), I only get
about 30k iops in total! With size=2. And I can't say that anything improved when I
upgraded from Nautilus to Octopus...