I’m passing through a WD SN850 via PCIe to a Windows 10 VM.
I’m seeing only 60MB/s random 4k reads, compared to >80MB/s with baremetal VM on same system. Similiar drop on random 4k writes too. I’d expect there to be some reduction, but much smaller.
I can’t seem to find any way to reduce that 25% gap.
Sequential reads/writes are unaffected, so it seems there’s some significant latency between the drive and the VM. I’ve no idea what component I need to tweak here.