linux-kernel - Re: [PATCH v2] Port hierarchical_{memory,swap}

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

Message-ID: <ked455hccs23ghrqug3ieqck6qmmlip5htgszjvz7n3cvhvaeo@7kkg6faezy2a>
Date: Mon, 12 Feb 2024 16:00:36 +0100
From: Michal Koutný <mkoutny@...e.com>
To: "Jan Kratochvil (Azul)" <jkratochvil@...l.com>
Cc: cgroups@...r.kernel.org, linux-kernel@...r.kernel.org, 
	linux-mm@...ck.org, containers@...ts.osdl.org, Waiman Long <longman@...hat.com>
Subject: Re: [PATCH v2] Port hierarchical_{memory,swap}_limit cgroup1->cgroup2

Hello.

Something like this would come quite handy.

On Mon, Feb 12, 2024 at 12:10:38PM +0800, "Jan Kratochvil (Azul)" <jkratochvil@...l.com> wrote:
> which are useful for userland to easily and performance-wise find out the
> effective cgroup limits being applied.

And the only way to figure out inside cgroupns.

> But for cgroup2 it has been missing so far, this is just a copy-paste of the
> cgroup1 code while changing s/memsw/swap/ as that is what cgroup1 vs. cgroup2
> tracks. I have added it to the end of "memory.stat" to prevent possible
> compatibility problems with existing code parsing that file.

I was thinking of memory.max.effective (and others).

- no need to (possibly flush) stats when reading memory.stat
- can be generalized also for pids controller (and other "limiting" controllers) 
- analogous to precedent of cpuset.cpus.effective

Whereas, using v1 approach in v2:
- memory.stat mixes true stats and limits,
- memmory.stat is hierarchical by default, no need for the prefix.

What do you think of the separate .effective file(s)?

Thanks
Michal

Download attachment "signature.asc" of type "application/pgp-signature" (229 bytes)