From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-bw0-f219.google.com ([209.85.218.219]:33195 "EHLO mail-bw0-f219.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751175AbZHHIZN (ORCPT ); Sat, 8 Aug 2009 04:25:13 -0400 Received: by bwz19 with SMTP id 19so1820481bwz.37 for ; Sat, 08 Aug 2009 01:25:13 -0700 (PDT) To: Reinette Chatre Cc: linville@tuxdriver.com, linux-wireless@vger.kernel.org, ipw3945-devel@lists.sourceforge.net, Wey-Yi Guy Subject: Re: [PATCH 16/16] iwlwifi: disable powersave mode References: <1249684912-22936-1-git-send-email-reinette.chatre@intel.com> <1249684912-22936-17-git-send-email-reinette.chatre@intel.com> From: Kalle Valo Date: Sat, 08 Aug 2009 11:25:09 +0300 In-Reply-To: <1249684912-22936-17-git-send-email-reinette.chatre@intel.com> (Reinette Chatre's message of "Fri\, 7 Aug 2009 15\:41\:52 -0700") Message-ID: <878whun256.fsf@litku.valot.fi> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-wireless-owner@vger.kernel.org List-ID: Reinette Chatre writes: > From: Wey-Yi Guy > > The enabling of powersaving had a big impact on reliability and > performance. Throughput on n band suffered especially. With power save > support enabled we see significant ping response times, dropped frames, and > reduced throughput. These are captured in the following bug reports: > > http://bugzilla.intellinuxwireless.org/show_bug.cgi?id=2051 > http://bugzilla.intellinuxwireless.org/show_bug.cgi?id=2053 > > Disable power save by default, add "iwl_support_ps" module parameter > that can be used to enable it again. You are again creating driver specific parameters. But we should be moving away from this and instead use just generic interfaces. Please, think three times (or even more) whenever creating new driver specific interfaces, be it module parameters, sysfs files etc.. It's a maintenance nightmare and also very confusing for the users. We need to focus on nl80211 and make it work properly with all drivers. For the problem at hand, I see two options: 1. Users seeing the problem disable power save either via wext or with CONFIG_CFG80211_DEFAULT_PS and everyone else still can use power save. The issue will be investigated and fixed. If the AP is buggy, there isn't much we can do. 2. If you think the problem is widespread, remove IEEE80211_HW_SUPPORTS_PS from the driver, fix the issues and renable power save support. -- Kalle Valo