On Tue, 24.03.15 20:29, WaLyong Cho (walyong....@samsung.com) wrote: > Hi, > > In recent systemd(from some month ago), when a unit has a mask for cpu > or blockio or memory, this mask is also propagated to siblings by > unit_get_target_mask(). > According to some of comments, it seems intentional. > > Could anyone explain why?
I added this after talking to Tejun. It's basically what the kernel will effectively do in "sane behaviour" mode too. Basically, the kernel really wants to avoid having to compare individual processes against groups, because behaviour is unclear then. They want to comapre groups against groups and processes against processes, but not groups against processes, since in many cases behaviour is very unclear then. To avoid the ambighities this creates entirely the answer is to not allow this, and hence always propagate all controller memberships not only towards the root, but also sideways. > In our system, some of service have MemoryLimit= options. By this > options, all of other services also create its own cgroup in memory. In > mobile system(or some of other embedded system), this can be heavy load. > > If this can be configurable, how about add a configuration for cgroup > mask propagation to siblings? The option for this will go away in the kernel too eventually, and we shouldn't intrdouce an option for behaviour we already know now we cannot support for long. I hope this makes some sense, Lennart -- Lennart Poettering, Red Hat _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
