From mboxrd@z Thu Jan  1 00:00:00 1970
Return-path: <linux-wireless-owner@vger.kernel.org>
Received: from he.sipsolutions.net ([78.46.109.217]:34976 "EHLO
	sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1756750Ab0LNHrU (ORCPT
	<rfc822;linux-wireless@vger.kernel.org>);
	Tue, 14 Dec 2010 02:47:20 -0500
Subject: Re: [RFC] mac80211: Change BA timeout
From: Johannes Berg <johannes@sipsolutions.net>
To: Sujith <m.sujith@gmail.com>
Cc: linux-wireless <linux-wireless@vger.kernel.org>
In-Reply-To: <19719.8288.322475.954293@gargle.gargle.HOWL>
References: <19719.8288.322475.954293@gargle.gargle.HOWL>
Content-Type: text/plain; charset="UTF-8"
Date: Tue, 14 Dec 2010 08:47:15 +0100
Message-ID: <1292312835.3569.5.camel@jlt3.sipsolutions.net>
Mime-Version: 1.0
Sender: linux-wireless-owner@vger.kernel.org
List-ID: <linux-wireless.vger.kernel.org>

On Tue, 2010-12-14 at 13:14 +0530, Sujith wrote:
> The BlockAck session timout value is currently an arbitrary 5000.
> This results in BA sessions being created and torn down incessantly
> when mac80211 is used with a driver (say ath9k) in AP mode.
> 
> The 802.11 standard doesn't specify any default value for the timeout field.
> And there is no benefit to be gained by tearing down BA sessions and
> recreating them. The current value of 5000 doesn't cause any problems,
> but it is hard to find an AP/STA in the field that uses a non-zero timeout.

Please make it configurable in the request API. Each session consumes
one of a very limited number of hardware queues on iwlwifi, and once we
go to having multiple connected stations to it as an AP, it would be
good to time out idle sessions.

johannes