USB device activity when not mounted

Michael Powell nightrecon at
Thu Jun 14 11:41:58 UTC 2012

Polytropon wrote:

> On Wed, 13 Jun 2012 22:26:16 -0600, Gary Aitken wrote:
>> I can understand why I would see activity on a USB device
>> when it's first plugged in.  But why do I see continued
>> activity (i.e. the light blinks on a usb disk or memory stick)?
>> When I umount one of these, they keep being beat up on and
>> it makes me nervous...  At what point is it sync'd and safe
>> to unplug?  I assume when the umount returns, but what's going
>> on after that?
> I don't think that's a problem. I've got a USB stick here
> that has a blinkenlight as soon as it's powered on (plugged
> in), even if there is no reading / writing / mounting activity.
> After you've successfully performed umount, the USB stick _is_
> synced and can safely be removed, no matter what you assume
> the funny lights want to tell you.
> Maybe that's just a "modern feature" to make the USB stick "more
> entertaining". :-)

I think der Blinkenlights is a Windows thing - some Windows driver bit turns 
it on and off. When you click the 'safe to remove' thing it's supposed to 
turn it off to tell you it's OK to pull it out. Totally meaningless and 
useless 'feature' if you're not using Windows, aside from the entertainment.



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