linux-kernel - About cgroup memory limits

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 09 May 2012 15:37:37 -0300
From:	Andre Nathan <andre@...irati.com.br>
To:	linux-kernel@...r.kernel.org
Cc:	balbir@...ux.vnet.ibm.com, andre@...irati.com.br
Subject: About cgroup memory limits

Hello

I'm doing some tests with LXC and how it interacts with the memory
cgroup limits, more specifically the memory.limit_in_bytes control file.

Am I correct in my understanding of the memory cgroup documentation[1]
that the limit set in memory.limit_in_bytes is applied to the sum of the
fields 'cache', 'rss' and 'mapped_file' in the memory.stat file?

I am also trying to understand the values reported in memory.stat when
compared to the statistics in /proc/$PID/statm.

Below is the sum of each field in /proc/$PID/statm for every process
running inside a test container, converted to bytes:

       size  resident     share     text  lib       data  dt
  897208320  28741632  20500480  1171456    0  170676224   0

Compare this with the usage reports from memory.stat (fields total_*,
hierarchical_* and pg* omitted):

cache                     16834560
rss                       8192000
mapped_file               3743744
swap                      0
inactive_anon             0
active_anon               8192000
inactive_file             13996032
active_file               2838528
unevictable               0

Is there a way to reconcile these numbers somehow? I understand that the
fields from the two files represent different things. What I'm trying to
do is to combine, for example, the fields from memory.stat to
approximately reach what is displayed by statm.

Thank you in advance,
Andre

[1] http://www.kernel.org/doc/Documentation/cgroups/memory.txt

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/