From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maynard Johnson Subject: Re: --mmap-pages option seemingly has no effect to help with LOST samples Date: Fri, 22 Jun 2012 15:23:34 -0500 Message-ID: <4FE4D446.5000906@us.ibm.com> References: <4FD7ACB9.70205@us.ibm.com> <4FD7AF0C.1030300@gmail.com> <4FD8B32C.60608@us.ibm.com> <4FD8B641.9040907@gmail.com> <4FE49663.7000908@us.ibm.com> <4FE49A6F.7020503@gmail.com> <4FE4C589.5080802@us.ibm.com> <4FE4CB21.90005@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from e35.co.us.ibm.com ([32.97.110.153]:47126 "EHLO e35.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753807Ab2FVUXw (ORCPT ); Fri, 22 Jun 2012 16:23:52 -0400 Received: from /spool/local by e35.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 22 Jun 2012 14:23:52 -0600 Received: from d03relay05.boulder.ibm.com (d03relay05.boulder.ibm.com [9.17.195.107]) by d03dlp02.boulder.ibm.com (Postfix) with ESMTP id 945793E4004F for ; Fri, 22 Jun 2012 20:23:48 +0000 (WET) Received: from d03av01.boulder.ibm.com (d03av01.boulder.ibm.com [9.17.195.167]) by d03relay05.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q5MKNfYD226482 for ; Fri, 22 Jun 2012 14:23:42 -0600 Received: from d03av01.boulder.ibm.com (loopback [127.0.0.1]) by d03av01.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q5MKNd1n008453 for ; Fri, 22 Jun 2012 14:23:41 -0600 In-Reply-To: <4FE4CB21.90005@gmail.com> Sender: linux-perf-users-owner@vger.kernel.org List-ID: To: David Ahern Cc: linux-perf-users@vger.kernel.org, suka@us.ibm.com On 06/22/2012 02:44 PM, David Ahern wrote: > On 6/22/12 1:20 PM, Maynard Johnson wrote: >> I was seeing this on both my Intel Core 2 Duo and an IBM POWER7 server, both running RHEL 6.2. Also tried on another POWER7 running RHEL 6.3 beta, and got the same results. I found another POWER server that had RHEL 6.2 but was temporarily booted on a 3.5 kernel and ran the test there -- the counts were good there. :-) Just to be sure, I rebooted that system to the stock RHEL 6.2 kernel and reproduced the problem. So it seems there's an upstream fix for this. Can someone help me find the commit? > > emails crossing in the ether. > > 2.6.32 is real early in the perf history. I flipped a system to the Fedora 14 2.6.35.14 kernel -- and it does not handle multiple events either. With Arnaldo's last updates I did notice something curious about the events: Yes, I realize that 2.6.32 is early perf, but a lot of our customers are stuck with it. Too bad I didn't discover this before RHEL 6.3 GA'ed. Again, I'm hoping that someone in the perf community watching this list might be able to point to an upstream commit for the problem so we can push that fix into RHEL 6.4 (at least). Is there someone you would suggest to be cc'ed? -Maynard > > Aggregated stats: > TOTAL events: 13165 > MMAP events: 63 > COMM events: 2 > SAMPLE events: 13100 > cycles:HG stats: > TOTAL events: 5769 > MMAP events: 63 > COMM events: 2 > SAMPLE events: 5704 > instructions:HG stats: > TOTAL events: 7396 > SAMPLE events: 7396 > > The HG is wrong -- I did not put attributes on the event. So, re-running with uk: > > $ perf record -fo /tmp/perf.data -e cycles:uk -e instructions:uk -c 100000 /tmp/loop_1b_instructions > > And life turned out right: > Aggregated stats: > TOTAL events: 17967 > MMAP events: 63 > COMM events: 2 > EXIT events: 1 > SAMPLE events: 17901 > cycles:ku stats: > TOTAL events: 7862 > MMAP events: 63 > COMM events: 2 > EXIT events: 1 > SAMPLE events: 7796 > instructions:ku stats: > TOTAL events: 10105 > SAMPLE events: 10105 > > So, try adding :uk to your events. That made no noticeable difference. > > David >