Re: [lkp] [shmem] 071904e8df: meminfo.AnonHugePages +553.5% increase

From: Kirill A. Shutemov
Date: Thu Aug 04 2016 - 06:58:37 EST


On Thu, Aug 04, 2016 at 04:54:09PM +0800, kernel test robot wrote:
>
> FYI, we noticed meminfo.AnonHugePages +553.5% increase due to commit:
>
> commit 071904e8dfed9525f9da86523caf78b6da5f9e7e ("shmem: get_unmapped_area align huge page")
> https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
>
> in testcase: vm-scalability
> on test machine: 128 threads 4 Sockets Haswell-EP with 512G memory
> with following parameters:
>
> path_params: 300s-16G-shm-pread-rand-mt-performance
> run:
>
>
>
> Disclaimer:
> Results have been estimated based on internal Intel analysis and are provided
> for informational purposes only. Any difference in system hardware or software
> design or configuration may affect actual performance.
>
> Details are as below:
> -------------------------------------------------------------------------------------------------->
>
>
> To reproduce:
>
> git clone git://git.kernel.org/pub/scm/linux/kernel/git/wfg/lkp-tests.git
> cd lkp-tests
> bin/lkp install job.yaml # job file is attached in this email
> bin/lkp run job.yaml
>
> =========================================================================================
> compiler/cpufreq_governor/kconfig/rootfs/runtime/size/tbox_group/test/testcase:
> gcc-6/performance/x86_64-rhel/debian-x86_64-2015-02-07.cgz/300s/16G/lkp-hsw-4ep1/shm-pread-rand-mt/vm-scalability
>
> commit:
> 6a028aa3ca ("shmem: prepare huge= mount option and sysfs knob")
> 071904e8df ("shmem: get_unmapped_area align huge page")
>
> 6a028aa3ca32379e 071904e8dfed9525f9da86523c
> ---------------- --------------------------
> %stddev %change %stddev
> \ | \
> 20428 ± 9% +553.5% 133500 ± 7% meminfo.AnonHugePages
> 42717 ± 4% +261.3% 154340 ± 6% meminfo.AnonPages

Hm. That's strange. I didn't expect this commit change anything for anon
memory.

Do you see the same effect from the commit in Linus' tree?

--
Kirill A. Shutemov