From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gary Thomas Subject: Re: PM related performance degradation on OMAP3 Date: Thu, 12 Apr 2012 09:28:50 -0600 Message-ID: <4F86F4B2.3080101@mlbassoc.com> References: <4F859C5D.3090400@mlbassoc.com> <87hawqt6vt.fsf@ti.com> <4F86B227.90802@mlbassoc.com> <87aa2hjavi.fsf@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from hermes.mlbassoc.com ([64.234.241.98]:50382 "EHLO mail.chez-thomas.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934343Ab2DLP3H (ORCPT ); Thu, 12 Apr 2012 11:29:07 -0400 In-Reply-To: <87aa2hjavi.fsf@ti.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Kevin Hilman Cc: Grazvydas Ignotas , linux-omap@vger.kernel.org, Paul Walmsley On 2012-04-12 08:14, Kevin Hilman wrote: > Gary Thomas writes: > >> On 2012-04-11 13:17, Kevin Hilman wrote: >>> Gary Thomas writes: >>> >>> [...] >>> >>>> I fear I'm seeing similar problems with 3.3. I have my board (similar >>>> to the BeagleBoard) ported to 3.0 and 3.3. I'm seeing terrible network >>>> performance on 3.3. For example, if I use TFTP to download a large file >>>> (~35MB), I get this: >>>> 3.0: 42.5 sec >>>> 3.3: 625.0 sec >>>> That's a factor of 15 worse! >>> >>> This might not be the same problem. What is the NIC being used, and >>> does it have GPIO interrupts? >> >> My board uses SMSC911x with GPIO interrupt signal. > > OK, then your problem is almost certainly solved by my GPIO triggering > fix, and not related to Grazvytas' problem. > >>> >>> If it's using GPIO interrupts, then you likely need this patch from >>> mainline (v3.4-rc1) >> >> I tried to just pick up the patch you [sort of] quoted below, but had >> a hard time applying it to my kernel. I've tried to just pick up the >> latest files from the mainline kernel, but so far I've nothing that >> builds > > Oh, right. Sorry about that. Yeah, that patch actually has > dependencies on other GPIO changes that were queued for v3.4 (and not in > v3.3.) > > If you're on v3.3, just pull the branch below[1] which is based on > v3.3-rc2. Pulling that into a v3.3 should build just fine. > > Kevin > > [1] git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-omap-pm.git for_3.4/fixes/gpio This worked a treat, thanks. My network performance is better now, but still not what it was. The same TFTP transfer now takes 71 seconds, so about 50% slower than on the 3.0 kernel. Applying the second [unnamed] patch (arch/arm/mach-omap2/cpuidle34xx.c) made no difference. I am interested in having PM working as I'm designing a battery powered portable unit, so I need to keep pursuing this. Note: I noticed that when I built with CONFIG_PM off and no other changes, my EHCI USB didn't work properly. Should this be the case? Thanks again for your help -- ------------------------------------------------------------ Gary Thomas | Consulting for the MLB Associates | Embedded world ------------------------------------------------------------