From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kevin Hilman Subject: Re: PM related performance degradation on OMAP3 Date: Thu, 12 Apr 2012 11:08:09 -0700 Message-ID: <877gxk962e.fsf@ti.com> References: <4F859C5D.3090400@mlbassoc.com> <87hawqt6vt.fsf@ti.com> <4F86B227.90802@mlbassoc.com> <87aa2hjavi.fsf@ti.com> <4F86F4B2.3080101@mlbassoc.com> <87aa2ganwj.fsf@ti.com> <4F870C6D.3030203@mlbassoc.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from na3sys009aog117.obsmtp.com ([74.125.149.242]:47610 "EHLO na3sys009aog117.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933248Ab2DLSIN (ORCPT ); Thu, 12 Apr 2012 14:08:13 -0400 Received: by dajx4 with SMTP id x4so3128544daj.28 for ; Thu, 12 Apr 2012 11:08:11 -0700 (PDT) In-Reply-To: <4F870C6D.3030203@mlbassoc.com> (Gary Thomas's message of "Thu, 12 Apr 2012 11:10:05 -0600") Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Gary Thomas Cc: Grazvydas Ignotas , linux-omap@vger.kernel.org, Paul Walmsley , Felipe Balbi Gary Thomas writes: > On 2012-04-12 10:57, Kevin Hilman wrote: >> +Felipe for EHCI question >> >> Gary Thomas writes: >> >> [...] >> >>> 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. >> >> And does a CONFIG_PM=n kernel get you back to your v3.0 performance? > > Correct. > OK, I just tried your TFTP experiment on a 3530/Overo board with the same smsc911x NIC that has GPIO interrupts, and I don't see much difference between a PM-enabled v3.0 and a PM-enabled v3.3. Are you TFTP'ing the file to an MMC filesystem? Can you try to a ramdisk[1]? If you're using MMC, it could be MMC driver changes since v3.0 that are actually causing your performance hit. In my experiment, I TFTP'd a 24Mb file to a ramdisk, to make sure no other drivers were invovled, and didn't see any major differences between v3.0, v3.3, and v3.3 CONFIG_PM disabled. Below are my results. As you can see, all the results seem to be pretty close to the same. This test was not on a controlled, isolated network, so the differences are probably explained by other network activity: - v3.0 vanilla: PM enabled, CPUidle enabled - Received 25362406 bytes in 35.5 seconds - Received 25362406 bytes in 44.9 seconds - Received 25362406 bytes in 49.0 seconds - Received 25362406 bytes in 36.2 seconds - Received 25362406 bytes in 56.3 seconds - Received 25362406 bytes in 65.2 seconds - Received 25362406 bytes in 37.0 seconds - v3.3: PM enabled, CPUidle enabled + GPIO fix (my for_3.4/fixes/gpio branch) + smsc911x regulator boot fix (Tony's omap/fix-smsc911x-regulator branch) - Received 25362406 bytes in 32.1 seconds - Received 25362406 bytes in 29.8 seconds - Received 25362406 bytes in 33.5 seconds - Received 25362406 bytes in 44.5 seconds - Received 25362406 bytes in 39.2 seconds - Received 25362406 bytes in 57.0 seconds - Received 25362406 bytes in 49.6 seconds - v3.3: CONFIG_PM=n + branches above + fix from Grazvydas for !CONFIG_PM case: [PATCH] ARM: OMAP: sram: fix BUG in dpll code for !PM case + disable CONFIG_OMAP_WATCHDOG which fails to boot when CONFIG_PM=y - Received 25362406 bytes in 34.1 seconds - Received 25362406 bytes in 33.9 seconds - Received 25362406 bytes in 34.9 seconds - Received 25362406 bytes in 37.8 seconds - Received 25362406 bytes in 40.0 seconds - Received 25362406 bytes in 37.6 seconds - Received 25362406 bytes in 34.4 seconds Kevin [1] simple steps to make a ramdisk mkfs.ext2 /dev/ram0 mkdir /tmp/rd mount /dev/ram0 /tmp/rd cd /tmp/rd