Truth be told I'm not 100% sure if this is due to 6.9.x, but the issues did start when I upgraded so I figured I'd give it a shot in here. Prior to 6.9.x, I had zero locks since deploying my current hardware from a year ago. The only material config change since the upgrade was that I began using my nvme drive as my primary cache drive, whereas before it was sitting idle in my server via unassigned devices. Also I no longer use unassigned devices but single- and multi-disk pools.   At