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In say VirtualBox you can create a file backed on the physical disk, and attach it to the VM so the VM sees it as a NVMe drive. In my experience this is also o
by magicalhippo 3y ago
In say VirtualBox you can create a file backed on the physical disk, and attach it to the VM so the VM sees it as a NVMe drive.
In my experience this is also orders of magnitude slower that true direct access, ie PCIe pass-through, as all access has to pass through the VM storage driver and so could explain what is happening.
- bravetraveler 3y agoThe storage driver may have more impact on VBox. You can get very impressive results with 'virtio' on KVM
- magicalhippo 3y agoYeah I've yet to try that. I know I get a similar lack of performance with Bhyve (FreeBSD) using VirtIO, so it's not a given it's fast. I have no idea how AWS run their VMs, was just saying a slow storage driver could give such results.
- bravetraveler 3y ago> just saying a slow storage driver could give such results Oh, absolutely - not to contest that! There's a whole lot of academia on 'para-virtualized' and so on in this light. That's interesting to hear about FreeBSD; basically all of my experience has been with Linux/Windows.