Hi Vivek, > > I could see the priority inversion by running Vivek's script and I > > understand how RT requests has to be handled. I'll create a patch > > which makes dm-ioband cooperates with CFQ scheduler. However, do you > > think we need some kind of limitation on processes which belong to the > > RT class to prevent the processes from depleting bandwidth? > > I think to begin with, we can keep the same behavior as CFQ. An RT task > can starve other tasks. > > But we should provide two configurations and user can choose any one. > If RT task is in root group, it will starve other sibling tasks/groups. If > it is with-in a cgroup, then it will starve its sibling only with-in that > cgroup and will not impact other cgroups. > > What I mean is following. > > root > / \ > RT group1 > > In above configuration RT task will starve everybody else. > > root > / \ > group1 group2 > / \ > RT BE > > In above configuration RT task will starve only sibling in group1 but > will not starve the tasks in group2 or in root. Thanks for the suggestion. I'll try this way when dm-ioband supports hierarchical grouping. Thanks, Ryo Tsuruta -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
