On 5/30/07, William Lee Irwin III <[EMAIL PROTECTED]> wrote: > On Wed, May 30, 2007 at 12:14:55AM -0700, Andrew Morton wrote: > > So how do we do this? > > Is there any sneaky way in which we can modify the kernel so that this new > > code gets exercised more? Obviously, tossing init into some default > > system-wide container would be a start. But I wonder if we can be > > sneakier - for example, create a new container on each setuid(), toss the > > task into that. Or something along those lines? > > How about a container for each thread group, pgrp, session, and user? >
I've been thinking about this, and figured that it could be quite useful to be able to mount a container tree that groups tasks by userid or thread group - for doing per-user resource controls, for example, without having to write a controller that specifically handles the per-user case. One option would be to add a mount option, something like mount -t container -ogroupkey=<X> where X could be one of: uid, gid, pgrp, sid, tgid And put hooks in the various places where these ids could change, in order to move tasks between contaners as appropriate. But after some thought it seems to me that this is putting complexity in the kernel that probably doesn't belong there, and additionally is probably not sufficently flexible for some real-life situations. (E.g. the user wants all users in the "student" group to be lumped into the same container, but each user in the "professor" group gets their own container). So maybe this would be better handled in userspace? Have a daemon listing on a process connector socket, and move processes between containers based on notifications from the connector and user-defined rules. We'd probably also want to add some new connector events, such as PROC_EVENT_PGRP, and PROC_EVENT_SID A simple daemon that handles the case where we're classifying based on a single key with no complex rules shouldn't be too hard to write. It also sounds rather like the classification engine that ResourceGroups had originally in the kernel and moved to userspace, so I'll take a look at that and see if it's adaptable for this. Paul ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ ckrm-tech mailing list https://lists.sourceforge.net/lists/listinfo/ckrm-tech
