Return-path: Received: from mail.atheros.com ([12.36.123.2]:39769 "EHLO mail.atheros.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755944AbYISDBk (ORCPT ); Thu, 18 Sep 2008 23:01:40 -0400 Date: Thu, 18 Sep 2008 20:01:25 -0700 From: "Luis R. Rodriguez" To: Steven Noonan CC: Luis Rodriguez , Ingo Molnar , "ath9k-devel@lists.ath9k.org" , linux-wireless , LKML Subject: Re: [ath9k-devel] ath9k: massive unexplained latency in 2.6.27 (rc5, rc6, probably others) Message-ID: <20080919030125.GG7408@tesla> (sfid-20080919_050144_201244_05F40CC2) References: <43e72e890809181134ybbec8fdxcb2a466aa17fe390@mail.gmail.com> <43e72e890809181142n7738cd99g522e6688e68d11ce@mail.gmail.com> <43e72e890809181344q416b5944w3332ee5a33db048c@mail.gmail.com> <20080918220102.GE7408@tesla> <43e72e890809181508w5232a14ewbf2bf18fe90a92d5@mail.gmail.com> <43e72e890809181610h3a7729d8s4c8484d97b21932e@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" In-Reply-To: Sender: linux-wireless-owner@vger.kernel.org List-ID: On Thu, Sep 18, 2008 at 07:52:16PM -0700, Steven Noonan wrote: > This IRQ debugging is lots of fun. My /var/log/messages jumped in size > to 241MB. :) > > My test case was a file transfer that basically copies 50MB from a > remote machine's /dev/urandom and writes it to /dev/null locally. That > should be a pretty nice large RX. And jeez, I'm seeing tremendous > download speeds now and I have no idea what is different about my > configuration. I'm getting up to 24 megabit per second transfer rates > (actual), which is incredibly unusual for ath9k. > > I wasn't able to reproduce the IRQ problems on -tip or Linus' current > tree (both with the group rekeying fix applied, which may or may not > be a good idea for reproducing the issue). Even tried doing > rmmod/modprobe in fast succession multiple times. Couldn't get it to > throw up. > > I wonder... My rmmod/modprobe originally was used after the improper > group rekeying before in order to get it back to normal. Perhaps the > encryption has to go wonky before this IRQ issue surfaces? Another > possibility is the earlier mentioned "ACPI: EC: GPE storm detected, > disabling EC GPE". I don't know if it's related or not, but I haven't > waited for it to show up before testing. > > Oh well, if the IRQ problem resurfaces (or if I get a ridiculous > latency tomorrow morning with irqpoll off), I'll try to get some > useful data to help debug it. Thanks for testing, and glad to see this is resolved. Luis