Read/Write speeds in virtual machines?

I’d like to install Ubuntu on my workstation, and then run Windows in a virtual machine.

I want to create some ZFS storage that I will pass off to the VM. The drives would be 3 Samsung 980 Pro NVMe drives in Raid-Z.

I want to be able to use ZFS to back up the Windows drive, so I can’t just pass through the drives, themselves to the Windows VM.

What kind of read and write speeds can I expect in the Windows VM relative to what I could achieve on the host Ubuntu machine?

Setting up Ubuntu with ZFS storage using three Samsung 980 Pro NVMe drives in RAIDZ, and running Windows in a virtual machine, balances performance with ZFS features like snapshots for backups. While read and write speeds on the Ubuntu host will be high, expect some performance loss in the Windows VM due to virtualization overhead. This typically causes a 10-30% drop, resulting in estimated read speeds of 9,800-12,600 MB/s and write speeds of 3,500-4,500 MB/s in the VM. These figures are optimistic; actual performance depends on VM setup, host load, and workload. Despite this overhead, NVMe SSDs’ low latency should provide responsive VM performance. To optimize, use virtio drivers, allocate enough VM resources, and tune hypervisor and ZFS settings for your needs.

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