I think you need batching for the nvme doorbell alone at anything close to these kinds of rates... For some workloads it's not that hard to have that deep queu

I think you need batching for the nvme doorbell alone at anything close to these kinds of rates... For some workloads it's not that hard to have that deep queues. What's harder is to know when to use them and when not. There's really not enough information available to make any of this self-tuning.