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.)

-Toby

1: Actual writes, not cached -- which I think is Windows default for removable storage. But tested by writing far more data than the laptop has RAM, followed by quickly selecting "Safely eject the device".