Re: pidns: Make pid accounting and pid_max per namespace

[Zefan Li <lizefan@huawei.com>]

On 2015/10/9 18:29, Zhang Haoyu wrote:
> I started multiple docker containers in centos6.6(linux-2.6.32-504.16.2),
> and there's one bad program was running in one container.
> This program produced many child threads continuously without free, so more and
> more pid numbers were consumed by this program, until hitting the pix_max limit (32768
> default in my system ).
>
> What's worse is that containers and host share the pid numbers resource, so new program
> cannot be produced any more in host and other containers.
>
> And, I clone the upstream kernel source from
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> This problem is still there, I'm not sure.
>
> IMO, we should isolate the pid accounting and pid_max between pid namespaces,
> and make them per pidns.
> Below post had request for making pid_max per pidns.
> http://thread.gmane.org/gmane.linux.kernel/1108167/focus=1111210
>

Mainline kernel already supports per-cgroup pid limit, which should solve
your problem.