From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: multipart/mixed; boundary="===============5489361929176380670==" MIME-Version: 1.0 From: Huang, Ying To: lkp@lists.01.org Subject: Re: [lkp-robot] [sched, cpumask] 9475ceda45: -6% regression of hackbench.throughput Date: Wed, 17 May 2017 09:37:48 +0800 Message-ID: <87y3twntzn.fsf@yhuang-dev.intel.com> In-Reply-To: <20170517013255.GA27433@yexl-desktop> List-Id: --===============5489361929176380670== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Ye Xiaolong writes: > On 05/16, Peter Zijlstra wrote: >>On Tue, May 16, 2017 at 09:33:49AM +0800, kernel test robot wrote: >>> = >>> Greeting, >>> = >>> We noticed a -6% regression of hackbench.throughput due to commit: >>> = >>> commit: 9475ceda453545fc55b2ccf30b1fbed0e590fdca ("sched,cpumask: Expor= t for_each_cpu_wrap()") >>> https://git.kernel.org/cgit/linux/kernel/git/peterz/queue.git schd/wip >>> = >>> in testcase: hackbench >>> on test machine: 112 threads Skylake with 64G memory >> >>How many sockets does that have? 112 threads is 56 cores. With a 23 core >>part that gives 2 sockets. But 23 is a very weird number of cores to >>have on a part (also wikipedia doesn't yet list the SKX parts). >> > > Hi, ying > > The tbox is lkp-skl-sp1, how do I get the socket info for it? You can queue hwinfo.yaml for it and check lscpu result. Best Regards, Huang, Ying > Thanks, > Xiaolong > > >>> with following parameters: >>> = >>> nr_threads: 50% >>> mode: threads >>> ipc: socket >>> cpufreq_governor: performance >>> = >>> test-description: Hackbench is both a benchmark and a stress test for t= he Linux kernel scheduler. >>> test-url: https://github.com/linux-test-project/ltp/blob/master/testcas= es/kernel/sched/cfs-scheduler/hackbench.c >> >>> Details are as below: >>> -----------------------------------------------------------------------= ---------------------------> >>> = >>> = >>> To reproduce: >>> = >>> git clone https://github.com/01org/lkp-tests.git >>> cd lkp-tests >>> bin/lkp install job.yaml # job file is attached in this email >>> bin/lkp run job.yaml >>> = >>> testcase/path_params/tbox_group/run: hackbench/50%-threads-socket-perfo= rmance/lkp-skl-sp1 >>> = >> >>> = >>> hackbench.throughput >>> = >>> 145000 ++------------------------------------------------------------= -----+ >>> 140000 *+**.*.* *. .**.*.*.**.*.**.*.**.*. *.*.**. = .* | >>> | *.*.**.*.**.*.* * * *.**.= * *.* >>> 135000 ++ = | >>> 130000 ++ O OO O OO = | >>> | O OO OO O O O O = | >>> 125000 ++ O = | >>> 120000 ++ = | >>> 115000 ++ = | >>> | = | >>> 110000 ++ O = | >>> 105000 ++ = | >>> | O O OO = | >>> 100000 O+ O O O = | >>> 95000 ++------------------------------------------------------------= -----+ >> >> >>So what is 'hackbench.throughput' and how do you run it? My hackbench >>only gives a total time, like: >> >>$ perf bench sched messaging -g 50 -l 5000 >># Running 'sched/messaging' benchmark: >># 20 sender and receiver processes per group >># 50 groups =3D=3D 2000 processes run >> >> Total time: 5.302 [sec] >> >> >>And my numbers are nowhere stable enough to conclusively see a >>regression, but I can maybe see a 2% dip on my IVB-EP. >> >>And I so don't want to dig through your script mess again :/ --===============5489361929176380670==--