On Mon, Feb 14, 2011 at 6:12 AM, [email protected] <[email protected]> wrote: > Hi Lennart, > Thanks for the explanation. > IMHO, To re-enable user session 'cpu' sorting: > a) Desktop distributions disable GROUP_RT in the kernel, then no > rt_bandwidth, all RT-apps can be fully administrated under rtkit. > Or b) cpu cgroup controller should default make sub-cgroups share > rt_bandwidth with their parent.
RT is about determinism. You need to ensure that task will be able to respond in fixed time. If you allow arbitrary, unknown in advance, number of tasks share the same limited CPU share, you simply kill determinism. Personally I think that RT should be restricted to limited number of tasks that are known in advance; then it is responsibility of administrator to allocate their CPU share according to requirements. > > 2011/2/14 Lennart Poettering <[email protected]> >> >> >> I am not aware of any typical daemon we ship that would use RT >> scheduling hence we are keeping the default 'cpu' cgroup sorting for >> system daemons enabled. However user applications are more likely to use >> RT (for example PA does) and hence we have disabled this for sessions >> for now. >> and for reasons outlined above I think that either PA should not require RT to run, or we need dedicated system wide PA daemon that can be made RT :) _______________________________________________ systemd-devel mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/systemd-devel
