Hi Kazunaga, On Tue, Mar 4, 2008 at 9:39 PM, Kazunaga Ikeno <k-ikeno@xxxxxxxxxxxxx> wrote: > Hi - > > This is a patch of a new optional function for task assignment to cgroup, RFC. > > > == Purpose ================================================= > > To provide the function that leads a task, corresponding to the conditions specified > beforehand, to a specific cgroup directory. > This is something that's been discussed before, originally as part of CKRM with a complex rule engine in the kernel space. Basically, the general agreement was that it's a case where a simple API is going to be too simple for the majority of users, and a complex API that satisfies everyone is going to be too messy/heavyweight. This is something that can be done in a userspace daemon via the process events connector - when you get a PROC_EVENT_UID event, you can move the process into the appropriate cgroup (you may also need to check any recently-forked children). This also gives you more flexibility than you can have in the kernel - you can base your decision on more complex factors than simply the uid of the process. Dhaval Giani had a prototype implementation of such a daemon. Paul > > == Description ============================================= > > This patch provides the function that leads a task, corresponding to the conditions > specified beforehand, to a specific cgroup directory. > > Currently, this patch uses user-id as a condition to lead a task. On its I/F, > specifies user-id of a task and a cgroup directory. > > The task set to specified user-id will automatically lead to the cgroup directory. > (it is attached to specific cgroup) > > This function makes possible to attach a task to cgroup automatically when > specific user logs in, also to attach a task of a service which is set to > specific effective user-id to specific cgroup mechanically. > > This function is just option, all the functions of cgroup are the same. > Also the migration of a task between cgroup directories can do by rewriting pid > of a control tasks file, including a task leading by this option. > > It is able to enter two or more set of user-id and cgroup directory. > Specified cgroup directory may be the same or that may not be. > But it's not able to enter same user-id to plural cgroup directories to lead. > > > == Interface =============================================== > > /lead_option - control file of this option > > [example for reading a configuration] > > # cat /cgroup/lead_option > > uid:202 leadto:/cpuset/bar_cg > uid:201 leadto:/cpuset/foo_cg > > * nothing appears before assignment. > > [example for adding an entry] > - To lead a task(uid 201) to /cgroup/foo_cg > > # echo uid:201 leadto:/cpuset/foo_cg > /cpuset/lead_option > > * set a uid of task and cgroup dirctory to lead. > * Remake an entry uid to cgroup directory if set uid already exists. > > [example for delete an entry] > - To delete an entry of uid > > # echo uid:201 > /cpuset/lead_option > > * To delete a registration, omit "leadto:" token. > > > == Operation example (chronological order) ================== > > The follows is an example of the operation. > > # ############################ > # # Various confirmation before testing > # ############################ > # id > uid=0(root) gid=0(root) groups=0(root) > # df /cpuset > Filesystem 1K-blocks Used Available Use% Mounted on > none 0 0 0 - /cpuset > # more /proc/self/cgroup > cpuset:/ > # id foo > uid=201(foo) gid=100(users) groups=100(users) > # id bar > uid=202(foo) gid=100(users) groups=100(users) > # ############################ > # # Add an entry of user foo,bar > # ############################ > # echo uid:201 leadto:/cpuset/foo_cg > /cpuset/lead_option > # echo uid:202 leadto:/cpuset/bar_cg > /cpuset/lead_option > # more /cpuset/lead_option > uid:202 leadto:/cpuset/bar_cg > uid:201 leadto:/cpuset/foo_cg > # ############################ > # # Confirmation of the assignment of user foo,bar - (1) > # ############################ > # su - foo > $ more /proc/$$/cgroup > cpuset:/foo_cg > $ more /proc/self/cgroup > cpuset:/foo_cg > $ su bar --command "more /proc/self/cgroup" > cpuset:/bar_cg > $ exit > # ############################ > # # Delete an entry of user foo,bar > # ############################ > # echo uid:201 > /cpuset/lead_option > # echo uid:202 > /cpuset/lead_option > # more /cpuset/lead_option > # ############################ > # # Confirmation of the assignment of user foo,bar - (2) > # ############################ > # su - foo > $ more /proc/$$/cgroup > cpuset:/ > $ su bar --command "more /proc/self/cgroup" > cpuset:/ > $ > > > Thanks, > - Kazunaga Ikeno. > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers