[aliguori]

It's exactly the same as with the i3.16xlarge instance type. There are eight 1900 GB drives. In an i3.16xlarge, those eight drives are passed through to the instance with PCIe passthrough but for the i3.metal instance, you avoid going through a hypervisor and IOMMU and have direct access.

[will_hughes]

Thanks.

I guess some other open questions:

- If one of those drives fails, will Amazon hotswap them out, or do you need to migrate to a new instance (moving TBs of data to a new box without causing outages can be painful.)

- Is there a hardware RAID controller for those drives, or is it software only?

- Can anyone with access to one of these boxes produce some IO performance stats on them? Bonus points for stats on single drive vs concurrent across all drives (i.e is there any throttling). More points for RAID10 performance across the whole 8.

[_msw_]

The local NVMe storage for i3.metal is the same as i3.16xlarge. There are 8 NVMe PCI devices. For i3.16xlarge those PCI devices are assigned to the instance running under the Xen hypervisor. When running i3.metal, there simply isn't a hypervisor and the PCI devices are accessed directly.

- There is no hot swap for the NVMe storage.

- The 8 NVMe devices are discrete, there is no hardware RAID controller

- Anyone can get I/O performance stats on i3.16xlarge as a baseline. Intel VT-d can introduce some overhead from the handling (and caching) of DMA remapping requests in the IOMMU and interrupt delivery so I/O performance may be a bit higher on i3.metal, with a few microseconds lower latency.