wiki:nvme

Version 1 (modified by Ryan Erbstoesser, 8 months ago) (diff)

start nvme page

NVME Solid State Storage

NVME (nonvolatile memory express) storage is a solid state storage option to be was primarily started for use in consumer laptops but is also able to be used on Gateworks SBCs.

This is different than mSATA discussed here

Note Venice SBCs don't support mSATA, thus the desire for NVME support.

Signals

The biggest thing to note about NVME is that it typically uses QTY 4 PCIe lanes for super high speeds. However, Gateworks SBCs have Mini-PCIe slots that have a single PCIe lane. Thus, the speeds are reduced while using the Gateworks SBCs compared to the full potential, but speeds are still very fast at around 225-275MB/s.

Sizes

Typical NVME sizes are 22mm wide. Some lengths quite long, designed for consumer laptops. (80mm long, 2280 defined size) These longer sizes are not ideal for the Gateworks SBCs.

Thus, for a Gateworks SBC, common sizes that would be compatible are a 2230 & 2242

M.2 Keys

Gateworks has created an M.2 adapter for Mini-PCIe slots, but the first adapter was designed for cellular modems which often take the B-Key.

Most NVME drives are M-Key. Gateworks plans to create an M-Key M.2 adapter for Mini-PCIe. Please contact Gateworks for more information.

Speeds

As mentioned above, Gateworks SBCs only expose 1x PCIe lane per slot, thus the speeds achieved will not be the same as on an x86 desktop with a full 4x PCIe lanes.

However, the speeds achieved are still often higher than even the onboard eMMC storage as discussed here

Gateworks has ran some sample speed tests using a GW73xx Venice SBC (PCIe Gen 2) and the following command:

dd if=/dev/nvme0n1 of=/dev/null bs=1M count=500 iflag=nocache
Drive Speed Notes
Samsung SSD980 ~225 Megabytes/sec 2280 size, no proper adapter
Silicon Motion MD681GEDKAF3 ~240 Megabytes/sec 2242 size