Return-path: Received: from mail-la0-f46.google.com ([209.85.215.46]:44128 "EHLO mail-la0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751346AbaHaR0g (ORCPT ); Sun, 31 Aug 2014 13:26:36 -0400 Received: by mail-la0-f46.google.com with SMTP id pv20so4980912lab.19 for ; Sun, 31 Aug 2014 10:26:35 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20140829145002.GA28486@sig21.net> References: <53D7AEF5.5040907@lwfinger.net> <20140730110829.GA3563@sig21.net> <20140829145002.GA28486@sig21.net> Date: Sun, 31 Aug 2014 20:26:34 +0300 Message-ID: (sfid-20140831_192735_432319_AE0B671B) Subject: Re: Poor wifi performance on Intel 7260 Dual-Band AC Wifi card From: Emmanuel Grumbach To: Johannes Stezenbach Cc: Nate Carlson , "linux-wireless@vger.kernel.org" , Larry Finger , Borislav Boev , "ilw@linux.intel.com" Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Fri, Aug 29, 2014 at 5:50 PM, Johannes Stezenbach wrote: > On Wed, Jul 30, 2014 at 01:08:30PM +0200, Johannes Stezenbach wrote: >> The question is how to go about testing. ISTR the Windows 8 driver >> didn't have any issue and gave decent speed, but I don't have the >> time to restore the Windows image for testing now. If Windows >> and Linux use the same firmware I guess a comparison would >> reveal if it's a driver of firmware issue. > > I had some spare time today to restore the Windows 8 image > and test (praise Clonezilla!). The test is with an AP which > (sometimes) sends broken beacons, so the result might not be viewed > as valid by some, but I'm just comparing performance of > different hardware and software under the same conditions. > https://bugzilla.kernel.org/show_bug.cgi?id=78101 > > Earlier today I could connect with Linux and the > Dual Band Wireless-AC 7260 gave me <50KB/s download > speed (fetching kernel tarball from PC connected via > 1G ethernet to the AP). An rt2800 usb dongle on the > same machine gave me ~2.5MB/s. Currently Linux > cannot connect at all (see bug 78101) due to the > broken beacon. > > With Windows 8 (Driver Version 16.10.0.5, Driver Date 1/28/2014) > I had no problems to connect, and got ~400KB/s download speed. > (I confirmed via capture on the PC that the beacons > were broken in the way described in bug 78101 during this test.) > The rt2800 usb dongle gave me 2.4MB/s in Windows. > > I couldn't reboot the AP today to see if and how much > the performance improves when the beacons are not broken. > I'll do that when I have time. In the past, rebooting > the AP did fix the connection issue (good beacon for some time), > but did not turn the AC 7260 into a speed demon with the > Linux driver. > > The AP only supports 2.4Ghz band 802.11n. > >> Otherwise I'm hoping Intel guys could provide some guidance for >> testing so we could find the root cause. > > So far Intel did not show much interest in the issue, but > a laptop user often has no control on the AP (travelling, > hotels, conferences, etc.). IMHO Intel would their users > a big favor if they spent some time optimizing for bad > network conditions. The broken AP on my side will be > replaced soon, but that's not the point of my complaint. > > So far - I was busy with other stuff - and will still be. After all, debugging issues we have with a completely broken AP isn't my top priority. And just for the record - can you share the progress you are having with the AP manufacturer? After all - this is the real bug - but you seem to complain about Intel more than the AP manufacturer... Strange isn't it?