Re: [LKP] Re: [mm/memcg] bd0b230fe1: will-it-scale.per_process_ops -22.7% regression

From: Rong Chen
Date: Mon Nov 02 2020 - 04:54:15 EST




On 11/2/20 5:27 PM, Michal Hocko wrote:
On Mon 02-11-20 17:15:43, kernel test robot wrote:
Greeting,

FYI, we noticed a -22.7% regression of will-it-scale.per_process_ops due to commit:


commit: bd0b230fe14554bfffbae54e19038716f96f5a41 ("mm/memcg: unify swap and memsw page counters")
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master
I really fail to see how this can be anything else than a data structure
layout change. There is one counter less.

btw. are cgroups configured at all? What would be the configuration?

Hi Michal,

We used the default configure of cgroups, not sure what configuration you want,
could you give me more details? and here is the cgroup info of will-it-scale process:

$ cat /proc/3042/cgroup
12:hugetlb:/
11:memory:/system.slice/lkp-bootstrap.service
10:devices:/system.slice/lkp-bootstrap.service
9:cpuset:/
8:perf_event:/
7:rdma:/
6:freezer:/
5:pids:/system.slice/lkp-bootstrap.service
4:net_cls,net_prio:/
3:blkio:/
2:cpu,cpuacct:/
1:name=systemd:/system.slice/lkp-bootstrap.service

Best Regards,
Rong Chen