Toby Corkindale via luv-main <luv-main@luv.asn.au> writes:
Hi, I've hit a strange issue with a new USB storage device. (Corsair Slider X2 64GB)
On a Windows 10 laptop, it'll happily get ~75mbyte/sec writes.[1] Reads are even faster.
However on my Linux workstation the best I can get is 27 mbyte/sec, and the usual speed more like 9-10 mbyte/sec. ie. Awful. Reads aren't much better, at 37mbyte/sec.
The same workstation can happily read and write very fast to other USB 3 storage devices, so I know the USB 3 ports are active.
I've tested with vfat, ext4, btrfs and ntfs filesystems, plus just plain using "dd" to write to the raw device. In all cases, performance is terrible.
I've played with mount options (sync, async, direct io, journal modes, etc) and it doesn't make a huge difference.
I don't suppose anyone else has hit this, and might have a fix?
(I'll test on an alternative Linux system tonight, with a slightly different Linux kernel and motherboard.)
Brainstorm things to check: * remove any unnecessary components e.g. USB hubs from the environment. * does dmesg complain about it? * does it draw too much power for that port? * are other port blocks (different chipset &c) OK? e.g. front panel is often worse. * Is it DEFINITELY doing more than USB2 theoretical max? Compare the speed you get to the max speed of USB2 and USB3. (IIRC USB2.0 is 480mbps = 60MiB/s). * is power saving being auto-enabled ever time you plug in the device, by some crack-smoking udev rule? Remember to check the device *and* the internal hub. If powertop --auto is involved, remove it while testing. * is the system doing a lot of fsyncs &c at the time? this can break even unrelated filesystems IME. The place I hit it was doing a dpkg install (many many syncs) while under heavy RRD write load (random access). * faint hope, but does SMART work with the drive?