On 08/11/2011 05:55 PM, Daniel Lezcano wrote: > Hi all, > > the cgroup cpuset and memory reduce access to a part of the resources on > the system. Some applications use the /proc/cpuinfo and /proc/meminfo to > allocate the resources. For instance, HPC jobs look at /proc/cpuinfo to > fork the number of cpu found in this file either look at /proc/meminfo > to allocate a big chunk of memory. Each process set the affinity on each > cpu, which in case a subset of cpus is used, some affinity will fail. > > In the case of the container, the cgroup is used to reduce the memory or > to assign a cpu to the container. Unfortunately, as this partitioning is > not reflected in /proc, the different system tools (ps, top, free, ...) > show a wrong information. > > I was wondering if that would make sense to create for the different > cgroup subsystem, when it is relevant, a proc formatted file we can bind > mount /proc. > > For example: /cgroup/memory.proc and /cgroup/cpuset.proc Not only that. user/sys/nice,etc statistics also are expected to be different than the main system one, among other things. One way I was thinking of doing it, was to always show per-cgroup data in /proc files when relevant, using the cgroup of the current process as a base. bind mounting proc files from their cgroup is a nice alternative, though. But it leaves the possibility of any user of it not setting it up. Although it is certainly more flexible, it makes me wonder if a constrained process should ever know about resources it can't access... If bind mounts are used, I'd suggest we represent them as directories, like cpuset.proc/cpuinfo. (It is not clear for me what exactly you meant in your proposal, sorry if it was just that). This might make things easier to setup an isolated /proc, since we can convention that anything in this format is available to be bind mounted, instead of having to convention that /cgroup/cpuset.proc means /proc/cpuinfo (May matter for future features) > Any ideas ? > > -- Daniel > > > _______________________________________________ > Containers mailing list > Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx > https://lists.linux-foundation.org/mailman/listinfo/containers _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers
