From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xiao Guangrong Subject: Re: [PATCH] add PLE stats to kvmstat Date: Sat, 07 Jul 2012 01:40:56 +0800 Message-ID: <4FF72328.4060907@gmail.com> References: <1341525037.12425.46.camel@oc2024037011.ibm.com> <4FF69703.9080402@linux.vnet.ibm.com> <1341580976.12425.50.camel@oc2024037011.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Xiao Guangrong , kvm@vger.kernel.org To: habanero@linux.vnet.ibm.com Return-path: Received: from mail-pb0-f46.google.com ([209.85.160.46]:64306 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757859Ab2GFRlB (ORCPT ); Fri, 6 Jul 2012 13:41:01 -0400 Received: by pbbrp8 with SMTP id rp8so14931935pbb.19 for ; Fri, 06 Jul 2012 10:41:01 -0700 (PDT) In-Reply-To: <1341580976.12425.50.camel@oc2024037011.ibm.com> Sender: kvm-owner@vger.kernel.org List-ID: On 07/06/2012 09:22 PM, Andrew Theurer wrote: > On Fri, 2012-07-06 at 15:42 +0800, Xiao Guangrong wrote: >> On 07/06/2012 05:50 AM, Andrew Theurer wrote: >>> I, and I expect others, have a keen interest in knowing how often we >>> exit for PLE, and also how often that includes a yielding to another >>> vcpu. The following adds two more counters to kvmstat to track the >>> exits and the vcpu yields. This in no way changes PLE behavior, just >>> helps us track what's going on. >>> >> >> Tracepoint is a better choice than the counters you used. :) > > Xiao, is kvmstat considered to be deprecated? Or are debug stats like > this just generally favored to be processed via something like perf > instead of debugfs? Andrew, please refer to Documentation/feature-removal-schedule.txt, it says: What: KVM debugfs statistics When: 2013 Why: KVM tracepoints provide mostly equivalent information in a much more flexible fashion. You can use tracepoints instead of your debugfs-counters in this patch. > Should we be removing kvmstat? > Some months ago, i implemented 'perf kvm-events' which can analyse kvm events more smartly, the patchset can be found at: https://lkml.org/lkml/2012/3/6/86 Avi said it may instead of kvmstat, but i am too busy to update this patchset. :)