From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D9D7E2C84D for ; Fri, 13 Oct 2023 23:03:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ZUTjQumT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 08918C433C8; Fri, 13 Oct 2023 23:03:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1697238217; bh=iqMnf/BMDJwzFbazhNU1KYWGcCmtvvfRHnstjXFUjjI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ZUTjQumTZ1JveX+KrzUF3EwwZD/Pxno1XqLO1TzfKno1IuxXHIs3vOK/nIfwOPdL/ xeNNkczh+TtrWXDVYrRIdnn7+9im/UhKjbxO6iuLlPojtaRryOFXJoj3ncg/btA51H lhaub5grrZ5APfH3VqKgGNR8JfXkMfVrdtn2irjS/dpnBUjVLtwerlQSXIHgak5Pv5 aKfZi82HsYKYQfNcZ2efxAUVK+KngZj4/7R0Z0j+zymh8hBKyEPLkcJkQC+pRtV6M0 +Gqolbt6tMZKLKv/MzdjR5NT1zKtUfu4QvQbUKXDYp8KHYD5JgCWH0+nCMHY9uYnNs cHFmtLLXJ9qow== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id 32A7D40016; Fri, 13 Oct 2023 20:03:34 -0300 (-03) Date: Fri, 13 Oct 2023 20:03:34 -0300 From: Arnaldo Carvalho de Melo To: Namhyung Kim Cc: Jiri Olsa , Ian Rogers , Adrian Hunter , Peter Zijlstra , Ingo Molnar , LKML , linux-perf-users@vger.kernel.org Subject: Re: [PATCH] perf bench sched pipe: Add -G/--cgroups option Message-ID: References: <20231004204741.985422-1-namhyung@kernel.org> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Url: http://acmel.wordpress.com Em Fri, Oct 13, 2023 at 03:57:27PM -0700, Namhyung Kim escreveu: > Hi Arnaldo, > > On Fri, Oct 13, 2023 at 3:41 PM Arnaldo Carvalho de Melo > wrote: > > > > Em Wed, Oct 04, 2023 at 01:47:41PM -0700, Namhyung Kim escreveu: > > > The -G/--cgroups option is to put sender and receiver in different > > > cgroups in order to measure cgroup context switch overheads. > > > > > > Users need to make sure the cgroups exist and accessible. > > > > > > # perf stat -e context-switches,cgroup-switches \ > > > > taskset -c 0 perf bench sched pipe -l 10000 > /dev/null > > > > > > Performance counter stats for 'taskset -c 0 perf bench sched pipe -l 10000': > > > > > > 20,001 context-switches > > > 2 cgroup-switches > > > > > > 0.053449651 seconds time elapsed > > > > > > 0.011286000 seconds user > > > 0.041869000 seconds sys > > > > > > # perf stat -e context-switches,cgroup-switches \ > > > > taskset -c 0 perf bench sched pipe -l 10000 -G AAA,BBB > /dev/null > > > > > > Performance counter stats for 'taskset -c 0 perf bench sched pipe -l 10000 -G AAA,BBB': > > > > > > 20,001 context-switches > > > 20,001 cgroup-switches > > > > > > 0.052768627 seconds time elapsed > > > > So I tried with: > > > > [root@quaco ~]# perf bench sched pipe -G system.slice,user.slice > > # Running 'sched/pipe' benchmark: > > cannot enter to cgroup: system.slice > > cannot enter to cgroup: user.slice > > # Executed 1000000 pipe operations between two processes > > > > Total time: 6.301 [sec] > > > > 6.301478 usecs/op > > 158692 ops/sec > > [root@quaco ~]# > > > > Should't it bail out when not managing to enter the cgroups? > > Hmm.. right. Will fix. > > > > > Also: > > > > [root@quaco ~]# mkdir /sys/fs/cgroup/AAA > > [root@quaco ~]# mkdir /sys/fs/cgroup/BBB > > [root@quaco ~]# > > [root@quaco ~]# perf bench sched pipe -G AAA,BBB > > # Running 'sched/pipe' benchmark: > > cannot enter to cgroup: AAA > > cannot enter to cgroup: BBB > > # Executed 1000000 pipe operations between two processes > > > > Total time: 6.397 [sec] > > > > 6.397830 usecs/op > > 156302 ops/sec > > [root@quaco ~]# > > > > -rw-r--r--. 1 root root 0 Oct 13 19:22 /sys/fs/cgroup/AAA/cgroup.procs > > [root@quaco ~]# ls -la /sys/fs/cgroup/AAA/cgroup.threads > > -rw-r--r--. 1 root root 0 Oct 13 19:22 /sys/fs/cgroup/AAA/cgroup.threads > > [root@quaco ~]# ls -la /sys/fs/cgroup/BBB/cgroup.threads > > -rw-r--r--. 1 root root 0 Oct 13 19:22 /sys/fs/cgroup/BBB/cgroup.threads > > [root@quaco ~]# ls -la /sys/fs/cgroup/BBB/cgroup.procs > > -rw-r--r--. 1 root root 0 Oct 13 19:22 /sys/fs/cgroup/BBB/cgroup.procs > > [root@quaco ~]# > > > > [root@quaco ~]# perf bench sched pipe -G AAA,BBB > > # Running 'sched/pipe' benchmark: > > cannot enter to cgroup: AAA (written=-1, len=6, errno=Operation not supported) > > cannot enter to cgroup: BBB (written=-1, len=6, errno=Operation not supported) > > # Executed 1000000 pipe operations between two processes > > > > Total time: 6.303 [sec] > > > > 6.303221 usecs/op > > 158649 ops/sec > > [root@quaco ~]# > > > > I'm certainly missing something here :-\ > > Try to enable some cgroup controllers first. Like > > # echo +cpu > /sys/fs/cgroup/AAA/cgroup.subtree_control > # echo +cpu > /sys/fs/cgroup/BBB/cgroup.subtree_control [root@quaco cgroup]# echo +cpu > /sys/fs/cgroup/AAA/cgroup.subtree_control [root@quaco cgroup]# echo +cpu > /sys/fs/cgroup/BBB/cgroup.subtree_control [root@quaco cgroup]# perf bench sched pipe -G AAA,BBB # Running 'sched/pipe' benchmark: cannot enter to cgroup: AAA (written=-1, len=6, errno=Operation not supported) cannot enter to cgroup: BBB (written=-1, len=6, errno=Operation not supported) # Executed 1000000 pipe operations between two processes Total time: 6.267 [sec] 6.267680 usecs/op 159548 ops/sec [root@quaco cgroup]# cat /sys/fs/cgroup/AAA/cgroup.subtree_control cpu [root@quaco cgroup]# cat /sys/fs/cgroup/BBB/cgroup.subtree_control cpu [root@quaco cgroup]# uname -a Linux quaco 6.5.6-200.fc38.x86_64 #1 SMP PREEMPT_DYNAMIC Fri Oct 6 19:02:35 UTC 2023 x86_64 GNU/Linux [root@quaco cgroup]#