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To: "M. Warner Losh" <imp@bsdimp.com>
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Cc: usb@freebsd.org, hackers@freebsd.org
Subject: Re: Help troubleshooting...
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M. Warner Losh wrote:
> I have a usb stick (8GB) on it.  This stick has about 5GB of junk on
> it at this point.
> 
> I tried to do 'cat * > /dev/null' recently, to measure how fast it
> goes.  It got about 1GB into the drive and then I got device missing
> messages.
		:
> So devfs thinks the device went missing:

Warner-san, maybe it is caused by the hardware problem on the USB flash 
memory. Some chip on the memory might have too much heat when you access 
the memory at fast rate. Then it stops working.

// Noriaki Mitsunaga