mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Vasily Averin <vvs@openvz.org>
To: "Michal Koutný" <mkoutny@suse.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>,
	Shakeel Butt <shakeelb@google.com>,
	kernel@openvz.org, linux-kernel@vger.kernel.org,
	Vlastimil Babka <vbabka@suse.cz>, Michal Hocko <mhocko@suse.com>,
	cgroups@vger.kernel.org
Subject: Re: [PATCH 3/4] memcg: enable accounting for struct cgroup
Date: Fri, 20 May 2022 23:16:32 +0300	[thread overview]
Message-ID: <d28233ee-bccb-7bc3-c2ec-461fd7f95e6a@openvz.org> (raw)
In-Reply-To: <740dfcb1-5c5f-6a40-0f71-65f277f976d6@openvz.org>

On 5/20/22 10:24, Vasily Averin wrote:
> On 5/19/22 19:53, Michal Koutný wrote:
>> On Fri, May 13, 2022 at 06:52:12PM +0300, Vasily Averin <vvs@openvz.org> wrote:
>>> Creating each new cgroup allocates 4Kb for struct cgroup. This is the
>>> largest memory allocation in this scenario and is epecially important
>>> for small VMs with 1-2 CPUs.
>>
>> What do you mean by this argument?
>>
>> (On bigger irons, the percpu components becomes dominant, e.g. struct
>> cgroup_rstat_cpu.)
> 
> Michal, Shakeel,
> thank you very much for your feedback, it helps me understand how to improve
> the methodology of my accounting analyze.
> I considered the general case and looked for places of maximum memory allocations.
> Now I think it would be better to split all called allocations into:
> - common part, called for any cgroup type (i.e. cgroup_mkdir and cgroup_create),
> - per-cgroup parts,
> and focus on 2 corner cases: for single CPU VMs and for "big irons".
> It helps to clarify which allocations are accounting-important and which ones
> can be safely ignored.
> 
> So right now I'm going to redo the calculations and hope it doesn't take long.

common part: 	~11Kb	+  318 bytes percpu
memcg: 		~17Kb	+ 4692 bytes percpu
cpu:		~2.5Kb	+ 1036 bytes percpu
cpuset:		~3Kb	+   12 bytes percpu
blkcg:		~3Kb	+   12 bytes percpu
pid:		~1.5Kb	+   12 bytes percpu		
perf:		 ~320b	+   60 bytes percpu
-------------------------------------------
total:		~38Kb	+ 6142 bytes percpu
currently accounted:	  4668 bytes percpu

Results:
a) I'll add accounting for cgroup_rstat_cpu and psi_group_cpu,
they are called in common part and consumes 288 bytes percpu.
b) It makes sense to add accounting for simple_xattr(), as Michal recommend,
 especially because it can grow over 4kb
c) it looks like the rest of the allocations can be ignored

Details are below
('=' -- already accounted, '+' -- to be accounted, '~' -- see KERNFS, '?' -- perhaps later )

common part:
16  ~   352     5632    5632    KERNFS (*)
1   +   4096    4096    9728    (cgroup_mkdir+0xe4)
1       584     584     10312   (radix_tree_node_alloc.constprop.0+0x89)
1       192     192     10504   (__d_alloc+0x29)
2       72      144     10648   (avc_alloc_node+0x27)
2       64      128     10776   (percpu_ref_init+0x6a)
1       64      64      10840   (memcg_list_lru_alloc+0x21a)

1   +   192     192     192     call_site=psi_cgroup_alloc+0x1e
1   +   96      96      288     call_site=cgroup_rstat_init+0x5f
2       12      24      312     call_site=percpu_ref_init+0x23
1       6       6       318     call_site=__percpu_counter_init+0x22

(*) KERNFS includes:
1   +  128      (__kernfs_new_node+0x4d)	kernfs node
1   +   88      (__kernfs_iattrs+0x57)		kernfs iattrs
1   +   96      (simple_xattr_alloc+0x28)	simple_xattr_alloc() that can grow over 4Kb 
1   ?   32      (simple_xattr_set+0x59)
1       8       (__kernfs_new_node+0x30)


memory:
------
1   +   8192    8192    8192    (mem_cgroup_css_alloc+0x4a)
14  ~   352     4928    13120   KERNFS
1   +   2048    2048    15168   (mem_cgroup_css_alloc+0xdd)
1       1024    1024    16192   (alloc_shrinker_info+0x79)
1       584     584     16776   (radix_tree_node_alloc.constprop.0+0x89)
2       64      128     16904   (percpu_ref_init+0x6a)
1       64      64      16968   (mem_cgroup_css_online+0x32)

1   =   3684    3684    3684    call_site=mem_cgroup_css_alloc+0x9e
1   =   984     984     4668    call_site=mem_cgroup_css_alloc+0xfd
2       12      24      4692    call_site=percpu_ref_init+0x23

cpu:
---
5   ~   352     1760    1760    KERNFS
1       640     640     2400    (sched_create_group+0x1b)
1       64      64      2464    (percpu_ref_init+0x6a)
1       32      32      2496    (alloc_fair_sched_group+0x55)
1       32      32      2528    (alloc_fair_sched_group+0x31)

4   +   512     512      512    (alloc_fair_sched_group+0x16c)
4   +   512     512     1024    (alloc_fair_sched_group+0x13e)
1       12      12      1036    call_site=percpu_ref_init+0x23

cpuset:
------
5   ~   352     1760    1760    KERNFS
1       1024    1024    2784    (cpuset_css_alloc+0x2f)
1       64      64      2848    (percpu_ref_init+0x6a)
3       8       24      2872    (alloc_cpumask_var_node+0x1f)

1       12      12      12      call_site=percpu_ref_init+0x23

blkcg:
-----
6   ~   352     2112    2112    KERNFS
1       512     512     2624    (blkcg_css_alloc+0x37)
1       64      64      2688    (percpu_ref_init+0x6a)
1       32      32      2720    (ioprio_alloc_cpd+0x39)
1       32      32      2752    (ioc_cpd_alloc+0x39)
1       32      32      2784    (blkcg_css_alloc+0x66)

1       12      12      12      call_site=percpu_ref_init+0x23

pid:
---
3   ~   352     1056    1056    KERNFS
1       512     512     1568    (pids_css_alloc+0x1b)
1       64      64      1632    (percpu_ref_init+0x6a)

1       12      12      12      call_site=percpu_ref_init+0x23

perf:
----
1       256     256     256     (perf_cgroup_css_alloc+0x1c)
1       64      64      320     (percpu_ref_init+0x6a)

1       48      48      48      call_site=perf_cgroup_css_alloc+0x33
1       12      12      60      call_site=percpu_ref_init+0x23

Thank you,
	Vasily Averin

  reply	other threads:[~2022-05-20 20:16 UTC|newest]

Thread overview: 139+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-04-27 10:37 [PATCH] memcg: accounting for objects allocated for new netdevice Vasily Averin
2022-04-27 14:01 ` Michal Koutný
2022-04-27 16:52   ` Shakeel Butt
2022-04-27 22:35     ` Vasily Averin
2022-05-02 12:15       ` [PATCH memcg v2] " Vasily Averin
2022-05-04 20:50         ` Luis Chamberlain
2022-05-05  3:50         ` patchwork-bot+netdevbpf
2022-05-11  2:51         ` Roman Gushchin
2022-05-02 19:37   ` kernfs memcg accounting Vasily Averin
2022-05-02 21:22     ` Michal Koutný
2022-05-04  9:00       ` Vasily Averin
2022-05-04 14:10         ` Michal Koutný
2022-05-04 21:16           ` Vasily Averin
2022-05-05  9:47             ` Michal Koutný
2022-05-06  8:37               ` Vasily Averin
2022-05-11  3:06         ` Roman Gushchin
2022-05-11  6:01           ` Vasily Averin
2022-05-11 16:49             ` Michal Koutný
2022-05-11 17:46             ` Roman Gushchin
2022-05-11 16:34           ` Michal Koutný
2022-05-11 18:10             ` Roman Gushchin
2022-05-13 15:51               ` [PATCH 0/4] memcg: accounting for objects allocated by mkdir cgroup Vasily Averin
2022-05-13 17:49                 ` Roman Gushchin
2022-05-21 16:37                   ` [PATCH mm v2 0/9] " Vasily Averin
2022-05-30 11:25                     ` [PATCH mm v3 " Vasily Averin
2022-05-30 11:55                       ` Michal Hocko
2022-05-30 13:09                         ` Vasily Averin
2022-05-30 14:22                           ` Michal Hocko
2022-05-30 19:58                             ` Vasily Averin
2022-05-31  7:16                               ` Michal Hocko
2022-06-01  3:43                                 ` Vasily Averin
2022-06-01  9:15                                   ` Michal Koutný
2022-06-01  9:32                                     ` Michal Hocko
2022-06-01 13:05                                       ` Michal Hocko
2022-06-01 14:22                                         ` Roman Gushchin
2022-06-01 15:24                                           ` Michal Hocko
2022-06-01  9:26                                   ` Michal Hocko
2022-06-13  5:34                       ` [PATCH mm v4 " Vasily Averin
2022-06-23 14:50                         ` [PATCH mm v5 0/9] memcg: accounting for objects allocated by mkdir, cgroup Vasily Averin
2022-06-23 15:03                           ` Vasily Averin
2022-06-23 16:07                             ` Michal Hocko
2022-06-23 16:55                               ` Shakeel Butt
2022-06-24 10:40                                 ` Vasily Averin
2022-06-24 12:26                                   ` Michal Koutný
2022-06-24 13:59                                 ` Michal Hocko
2022-06-25  9:43                                   ` [PATCH RFC] memcg: avoid idr ids space depletion Vasily Averin
2022-06-25 14:04                                   ` [PATCH RFC] memcg: notify about global mem_cgroup_id " Vasily Averin
2022-06-26  1:56                                     ` Roman Gushchin
2022-06-26  7:11                                       ` Vasily Averin
2022-06-27  2:12                                         ` [PATCH cgroup] cgroup: set the correct return code if hierarchy limits are reached Vasily Averin
2022-06-27  3:33                                           ` Muchun Song
2022-06-27  9:07                                           ` Tejun Heo
2022-06-28  0:44                                           ` Roman Gushchin
2022-06-28  3:59                                             ` Vasily Averin
2022-06-28  9:16                                               ` Michal Koutný
2022-06-28  9:22                                                 ` Tejun Heo
2022-06-29  6:13                                                   ` Vasily Averin
2022-06-29 19:25                                                     ` Tejun Heo
2022-07-01  2:42                                                       ` Roman Gushchin
2022-06-27  2:11                                       ` [PATCH mm v2] memcg: notify about global mem_cgroup_id space depletion Vasily Averin
2022-06-27  3:23                                         ` Muchun Song
2022-06-27  6:49                                           ` Vasily Averin
2022-06-28  1:11                                             ` Roman Gushchin
2022-06-28  3:43                                               ` Vasily Averin
2022-06-28  9:08                                               ` Michal Koutný
2022-06-27 16:37                                   ` [PATCH mm v5 0/9] memcg: accounting for objects allocated by mkdir, cgroup Shakeel Butt
2022-07-01 11:03                                     ` Michal Hocko
2022-07-10 18:53                                       ` Vasily Averin
2022-07-11 16:24                                         ` Michal Hocko
2022-06-23 14:50                         ` [PATCH mm v5 1/9] memcg: enable accounting for struct cgroup Vasily Averin
2022-06-23 14:50                         ` [PATCH mm v5 2/9] memcg: enable accounting for kernfs nodes Vasily Averin
2022-06-23 14:51                         ` [PATCH mm v5 3/9] memcg: enable accounting for kernfs iattrs Vasily Averin
2022-06-23 14:51                         ` [PATCH mm v5 4/9] memcg: enable accounting for struct simple_xattr Vasily Averin
2022-06-23 14:51                         ` [PATCH mm v5 5/9] memcg: enable accounting for percpu allocation of struct psi_group_cpu Vasily Averin
2022-06-23 14:51                         ` [PATCH mm v5 6/9] memcg: enable accounting for percpu allocation of struct cgroup_rstat_cpu Vasily Averin
2022-06-23 14:51                         ` [PATCH mm v5 7/9] memcg: enable accounting for large allocations in mem_cgroup_css_alloc Vasily Averin
2022-06-23 14:51                         ` [PATCH mm v5 8/9] memcg: enable accounting for allocations in alloc_fair_sched_group Vasily Averin
2022-06-23 14:52                         ` [PATCH mm v5 9/9] memcg: enable accounting for perpu allocation of struct rt_rq Vasily Averin
2022-06-13  5:34                       ` [PATCH mm v4 1/9] memcg: enable accounting for struct cgroup Vasily Averin
2022-06-13  5:34                       ` [PATCH mm v4 2/9] memcg: enable accounting for kernfs nodes Vasily Averin
2022-06-13  5:34                       ` [PATCH mm v4 3/9] memcg: enable accounting for kernfs iattrs Vasily Averin
2022-06-13  5:35                       ` [PATCH mm v4 4/9] memcg: enable accounting for struct simple_xattr Vasily Averin
2022-06-13  5:35                       ` [PATCH mm v4 5/9] memcg: enable accounting for percpu allocation of struct psi_group_cpu Vasily Averin
2022-06-13  5:35                       ` [PATCH mm v4 6/9] memcg: enable accounting for percpu allocation of struct cgroup_rstat_cpu Vasily Averin
2022-06-13  5:35                       ` [PATCH mm v4 7/9] memcg: enable accounting for large allocations in mem_cgroup_css_alloc Vasily Averin
2022-06-13  5:35                       ` [PATCH mm v4 8/9] memcg: enable accounting for allocations in alloc_fair_sched_group Vasily Averin
2022-06-13  5:35                       ` [PATCH mm v4 9/9] memcg: enable accounting for perpu allocation of struct rt_rq Vasily Averin
     [not found]                     ` <cover.1653899364.git.vvs@openvz.org>
2022-05-30 11:25                       ` [PATCH mm v3 1/9] memcg: enable accounting for struct cgroup Vasily Averin
2022-05-30 11:26                       ` [PATCH mm v3 2/9] memcg: enable accounting for kernfs nodes Vasily Averin
2022-05-30 11:26                       ` [PATCH mm v3 3/9] memcg: enable accounting for kernfs iattrs Vasily Averin
2022-05-30 11:26                       ` [PATCH mm v3 4/9] memcg: enable accounting for struct simple_xattr Vasily Averin
2022-05-30 11:26                       ` [PATCH mm v3 5/9] memcg: enable accounting for percpu allocation of struct psi_group_cpu Vasily Averin
2022-05-30 11:26                       ` [PATCH mm v3 6/9] memcg: enable accounting for percpu allocation of struct cgroup_rstat_cpu Vasily Averin
2022-05-30 15:04                         ` Muchun Song
2022-05-30 11:26                       ` [PATCH mm v3 7/9] memcg: enable accounting for large allocations in mem_cgroup_css_alloc Vasily Averin
2022-05-30 11:26                       ` [PATCH mm v3 8/9] memcg: enable accounting for allocations in alloc_fair_sched_group Vasily Averin
2022-05-30 11:27                       ` [PATCH mm v3 9/9] memcg: enable accounting for perpu allocation of struct rt_rq Vasily Averin
2022-05-30 15:06                         ` Muchun Song
2022-05-21 16:37                   ` [PATCH mm v2 1/9] memcg: enable accounting for struct cgroup Vasily Averin
2022-05-22  6:37                     ` Muchun Song
2022-05-21 16:37                   ` [PATCH mm v2 2/9] memcg: enable accounting for kernfs nodes Vasily Averin
2022-05-22  6:37                     ` Muchun Song
2022-05-21 16:37                   ` [PATCH mm v2 3/9] memcg: enable accounting for kernfs iattrs Vasily Averin
2022-05-22  6:38                     ` Muchun Song
2022-05-21 16:38                   ` [PATCH mm v2 4/9] memcg: enable accounting for struct simple_xattr Vasily Averin
2022-05-22  6:38                     ` Muchun Song
2022-05-21 16:38                   ` [PATCH mm v2 5/9] memcg: enable accounting for percpu allocation of struct psi_group_cpu Vasily Averin
2022-05-21 21:34                     ` Shakeel Butt
2022-05-22  6:40                     ` Muchun Song
2022-05-25  1:30                     ` Roman Gushchin
2022-05-21 16:38                   ` [PATCH mm v2 6/9] memcg: enable accounting for percpu allocation of struct cgroup_rstat_cpu Vasily Averin
2022-05-21 17:58                     ` Vasily Averin
2022-05-21 21:35                     ` Shakeel Butt
2022-05-21 22:05                     ` kernel test robot
2022-05-25  1:31                     ` Roman Gushchin
2022-05-21 16:38                   ` [PATCH mm v2 7/9] memcg: enable accounting for large allocations in mem_cgroup_css_alloc Vasily Averin
2022-05-22  6:47                     ` Muchun Song
2022-05-21 16:38                   ` [PATCH mm v2 8/9] memcg: enable accounting for allocations in alloc_fair_sched_group Vasily Averin
2022-05-22  6:49                     ` Muchun Song
2022-05-21 16:39                   ` [PATCH mm v2 9/9] memcg: enable accounting for percpu allocation of struct rt_rq Vasily Averin
2022-05-21 21:37                     ` Shakeel Butt
2022-05-25  1:31                     ` Roman Gushchin
2022-05-13 15:51               ` [PATCH 1/4] memcg: enable accounting for large allocations in mem_cgroup_css_alloc Vasily Averin
2022-05-19 16:46                 ` Michal Koutný
2022-05-20  1:07                 ` Shakeel Butt
2022-05-13 15:51               ` [PATCH 2/4] memcg: enable accounting for kernfs nodes and iattrs Vasily Averin
2022-05-19 16:33                 ` Michal Koutný
2022-05-20  1:12                 ` Shakeel Butt
2022-05-13 15:52               ` [PATCH 3/4] memcg: enable accounting for struct cgroup Vasily Averin
2022-05-19 16:53                 ` Michal Koutný
2022-05-20  7:24                   ` Vasily Averin
2022-05-20 20:16                     ` Vasily Averin [this message]
2022-05-21  0:55                       ` Roman Gushchin
2022-05-21  7:28                         ` Vasily Averin
2022-05-23 13:52                       ` Michal Koutný
2022-05-20  1:31                 ` Shakeel Butt
2022-05-13 15:52               ` [PATCH 4/4] memcg: enable accounting for allocations in alloc_fair_sched_group Vasily Averin
2022-05-19 16:45                 ` Michal Koutný
2022-05-20  1:18                 ` Shakeel Butt

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=d28233ee-bccb-7bc3-c2ec-461fd7f95e6a@openvz.org \
    --to=vvs@openvz.org \
    --cc=cgroups@vger.kernel.org \
    --cc=kernel@openvz.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mhocko@suse.com \
    --cc=mkoutny@suse.com \
    --cc=roman.gushchin@linux.dev \
    --cc=shakeelb@google.com \
    --cc=vbabka@suse.cz \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

Powered by JetHome