USB-3 xhci question

YuryG

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I have an USB-3 flash stick. And a motherboard with USB3 ports. At first, when I've inserted the stick, it showed SUPER speed. After unmount-detach-attach cycle it became only HIGH speed (i.e. USB2). Haven't managed to notice any error messages in dmesg or anywhere. What could be a reason for the problem?
/amd64 11.3-PRERELEASE r347510
 

aragats

Daemon

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Not a real answer:
Neither devices nor controllers follow USB standards for 100%, especially USB 3.x. All kinds of issues happen with any OS which support USB, in most cases they are not really noticeable to regular users.

Of course, maybe there is a real (known) bug in your case, and somebody may point to a solution/work-around.
 

aragats

Daemon

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speed drops multiple times during reattachment.
The nominal speed, right? The flash memory is significantly slower than USB. In sync mode it won't be noticeable, the async mode is not used unless explicitly specified.
 
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YuryG

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The nominal speed, right? The flash memory is significantly slower than USB. In sync mode it won't be noticeable, the async mode is not used unless explicitly specified.
I am not sure, I've got what you mean about sync/ async.
I'd say real speed. Reading speed. 90 MB/s vs 35 MB/s. Three times. I'm not expecting tremendous writing speed from flash. But reading could be quite fast.
 

tingo

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are you using the same usb port(s) in both cases? (ie super and high speed). It is common for motherboards to have both usb 3 and usb 2 ports, connected to separate controllers.
 
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YuryG

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are you using the same usb port(s) in both cases? (ie super and high speed). It is common for motherboards to have both usb 3 and usb 2 ports, connected to separate controllers.
Of course, the same USB socket of a blue colour.
 
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