Linux Tests Of The QNINE M.2 NVMe SSD Enclosure To USB-C Adapter

[torsionbar28]

Surely, you was not IT guy that time.... USB was a huge step forward over connecting the things over serial (or even parallel) port. Installing drivers for serial devices was troublesome and painful. Configuring programs to use them required much of configuration: setting baud-rate, number of stop bits, etc.

Sounds like you're confused here. RS232 devices do not require drivers. Their simplicity is why they are still in use today. Baud, data bits, parity, and stop are the only parameters. Not that you ever have to change them, as nearly everything uses 8/N/1. USB on the other hand, was a complicated cumbersome mess, where every device requires a driver, Windows users call this "driver hell". Remember when Bill Gates did a live demo of Windows 95? He plugged in a USB device and the whole OS crashed with BSOD, for the world to see. No such problems with RS232 serial. BTW my first PC was a Compaq 286 with 1200 baud modem...

USB was a huge step forward. USB 2.0 was finally something reliable and fast enough for most of the things of that time (maybe, not for you). Firewire was there but did not get widespread use. I never had a single device. Complain or not, it never got widespread use in circles around me, same as SCSI disks. Anyway, I am happy that you are finally happy with USB 3.1.

Incorrect, most pro audio/video equipment was firewire only. Because USB 2.0 was so crappy and slow, high bandwidth devices all came in Firewire versions, for people who care about performance. At one time, I had Firewire DVD burner, Firewire flat bed scanner, Firewire audio mixer, Firewire hard drives. It was a no brainer, really. If you like 30 MB/s, USB2 is ok for you. If you like 80 MB/s, Firewire delivers it. Did you think it was a coincidence that Apple used Firewire heavily, and also most media/design people used Apple? When you have large audio and video data to move around, USB2 was simply too slow.

But if 30 MB/s USB2 works for you, hey that's great for you. I'm just glad that after 23 years of waiting for v3.1, we finally have a USB that doesn't suck.

[edwaleni]

On the ASUS PRIME Z390A board, the 2nd M.2 slot can accept a properly keyed SATA SSD, but it will consume a resource from the onboard SATA controller. You have to enable it in the BIOS.

The JMicron NVMe to USB 3.1 Gen 2 controller uses 2 PCIe lanes (v3) to communicate with the SSD.

Based on Michael's tests, the adapter is fully using the maximum bandwidth available via the USB port and controller.

What I am concerned about is the 870EVO performance in the M.2 slot alone.

The Z390 has a very unique approach to USB control, especially between Gen 2 mode (where it needs to detect voltage on the C port) and Gen 1 and lower (A ports).

If it detects voltage on the C port it uses 20:f0, if it doesn't detect voltage it uses 20:f1 via the xDCI interface.

It sounds like Intel has essentially placed a USB switch and voltage detection determines the route on the PCIe bus.

[wagaf]

Thanks for the great review !

[darkbasic]

Huh? The product tested in this article does; the SSD tested in the article is an NVMe drive. To my knowledge, all NVMe drives also support SATA. If you want something that'll benefit from the extra performance of an NVMe drive's PCIe lanes, I think the overhead and abstraction of USB would diminish those returns.

The Amazon product page says it does not support SATA M.2 drives.

[PCJohn]

USB 3.1 is quite frankly the first iteration of USB that doesn't suck ass at storage. It only took what, 23 years to get here. yay?
v1.x was serial port replacement. v2.0 was stupid slow, no reason to use it over firewire. [...]

Surely, you was not IT guy that time.... USB was a huge step forward over connecting the things over serial (or even parallel) port. Installing drivers for serial devices was troublesome and painful. Configuring programs to use them required much of configuration: setting baud-rate, number of stop bits, etc. USB was a huge step forward. USB 2.0 was finally something reliable and fast enough for most of the things of that time (maybe, not for you). Firewire was there but did not get widespread use. I never had a single device. Complain or not, it never got widespread use in circles around me, same as SCSI disks. Anyway, I am happy that you are finally happy with USB 3.1.

[timrichardson]

A common reason to use an enclosure like this would be to clone an existing laptop SSD to a new one, and after cloning, taking the new drive out of the enclosure and into the laptop. Done that a few times with SATA drives. But I heard that NVMe enclosures don't work like this, for some reason: putting the drive into a the laptop requires reformatting it. Is this correct?

[torsionbar28]

[*]Does SMART work (E.g. by smartctl)? It is historically a problem with USB adapters.

USB 3.1 uses UASP for storage, so full SCSI command set is available. USB prior to 3.1 was junk, with junk protocols and implementations that were hit or miss on SMART. USB 3.1 fixes this mess finally.

[dwagner]

You can see the JMicron logo on thr chip. So I guess it's the JMS583.

You don't really have to guess, since that is currently the only NVMe <-> USB 3.1gen2 chip on the market.
German c't magazine recently tested two such external enclosures (paywalled: https://www.heise.de/select/ct/2018/21/1539398715074134 ) - with similar results: The connection is simply unstable with all enclosures using this chip, and not only under Linux.

I guess we'll have to wait for the ASMedia ASM2364 chip to hit the market before expecting different results.

[satan0rx]

You can see the JMicron logo on thr chip. So I guess it's the JMS583.

[Veto]

Interesting test!! Some additional questions:

• What type of interface/bridge IC is used and/or can we get a clearer picture of the backside of the board?
• What is the output of lsusb and dmesg?
• Does SMART work (E.g. by smartctl)? It is historically a problem with USB adapters.

Most likely the adapter is a reference design for the central interface IC and the random disconnects due to either a driver or chip error, related to this specific IC. Buying a different adapter based on the same chip is likely to have the same disconnects.