Date: Tue, 24 Apr 2012 00:21:06 -0500
From: Jonathan Nieder <jrnieder@gmail.com>
To: Ben Hutchings <ben@decadent.org.uk>
Cc: Richard Kettlewell <rjk@greenend.org.uk>,
	Johannes Stezenbach <js@sig21.net>,
	linux-wireless@vger.kernel.org, debian-kernel@lists.debian.org,
	Ivo Van Doorn <ivdoorn@gmail.com>
Subject: Re: High network latency with ralink usb wireless device
Message-ID: <20120424052106.GA19023@burratino> (sfid-20120424_072117_207421_A8D132A9)
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Hi Ben,

About a year ago, Richard Kettlewell wrote[1]:
> On 19/03/2011 22:31, Johannes Stezenbach wrote:

>> I sent a patch to disable power save by default, but then work started
>> to fix it instead, but then stalled.  Seems like 2.6.38 shipped with
>> broken power save enabled by default.  Plese read the discussion
>> following my RFC patch:
>> http://rt2x00.serialmonkey.com/pipermail/users_rt2x00.serialmonkey.com/2011-January/thread.html#3017
>>
>> You can test if power saving causes your issue by disabling
>> it with "iwconfig wlan0 power off".
>
> That does the trick - thanks!

Therefore ever since version 2.6.38-2, Debian kernels have had
powersaving disabled on rt2800usb devices.

I think we should revisit this in light of

  v3.0-rc2~7^2~16^2~190 rt2x00: Add autowake support for USB hardware
  (2011-04-30)

though I wouldn't be surprised if testing ends up revealing some
followup patches introduced after v3.2 to be needed for it to work
well.  What do you think?

Thanks,
Jonathan

[1] http://bugs.debian.org/618930