原创 Implementing boot test for flash usability

Non-volatile flash memory (NVMe) has been utilised to increase the performance of high-end servers for years, notably pioneered by Fusion IO. Today, NVMe is becoming the preferred technology for flash storage and the all-flash datacenter. As NVMe adoption increases, other elements of usability will allow this technology to increase its reach beyond the datacenter, including its use as a boot device.

In order to increase the usability of NVMe devices, the ability to boot off of an NVMe device is an important step. For enterprise devices, boot performance and timing aren't critical. Since these products are intended to be up 24/7, boot time is not a major concern. However, while NVMe is being introduced initially in the enterprise space, its sights are set on the client and mobile space (hence the emphasis on using the M.2 connector). In these product segments, boot time is critical. Thus, UNH-IOL in partnership with the NVM Express Organization has added an OS boot interoperability test to the NVMe Interoperability Test Suite.

Although today the test is optional, in the future it will likely become a mandatory part of the NVMe Integrators List qualification. Booting off of an NVMe device requires users to use UEFI instead of BIOS. What is UEFI? More information can be found at UEFI.org.

For our purposes, think of UEFI as a modern replacement for BIOS. While NVMe has had driver support in Linux and Windows for some time, only recently was NVMe support added to UEFI. BIOS support for NVMe is nonexistent, hence the need to use UEFI. With a UEFI NVMe driver, a system can be configured to boot off of an NVMe device. The UEFI Boot Manager is configured to look for the OS on the NVMe device. Then during the bring-up sequence, the UEFI driver will hand off to the OS driver (either Linux or Windows).

If you have access to an NVMe device and a system that supports UEFI, you can follow our test procedure to boot off of the NVMe device. (See PDF of Test 1.5 in the NVMe Interoperability Test Suite.)

Again, boot testing will be à la carte or an FYI test as part of the Interop Test Plan at the third NVMe Plugfest the week of November 10, hosted by the UNH-IOL. We encourage those attending to participate in this testing, since it will be mandatory in future plugfests.

David Woolf

UNH-IOL NVMe Consortium Lead