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Date: Tue, 25 Jul 2017 13:02:30 -0400 (EDT)
From: Alan Stern <stern@rowland.harvard.edu>
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To: Zdenek Kabelac <zkabelac@redhat.com>
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Subject: Re: USB disk speed regression WD Elements - with bisect result
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On Tue, 25 Jul 2017, Zdenek Kabelac wrote:

> And in fact it's the very same commit - which adds this message
> (just check current 4.13 with and without this commit reverted)
> 
> So here goes usbmon trace (aka  'cat /sys/kernel/debug/usb/usbmon/0u')
> no other usb device has been touch so should not hopefully interfere here.
> 
> Trace is from 4.12 kernel - so it has reported  "not running at top speed"

Can you collect an equivalent trace under 4.8?

Alan Stern