Re: [RFC, PATCH 0/5] Going forward with Resource Management - A cpucontroller

From: Kirill Korotaev
Date: Tue Aug 08 2006 - 03:14:51 EST

Doesnt the ability to move tasks between groups dynamically affect
(atleast) memory controller design (in giving up ownership etc)?

we save object owner on the object. So if you change the container,
objects are still correctly charged to the creator and are uncharged
correctly on free.

Seems like the object owner should also change when the object moves
from one container to another.

Consider a file which is opened in 2 processes. one of the processes
wants to move to another container then. How would you decide whether
to change the file owner or not?

If a process has sufficient rights to move a file to a new container
then it should be okay to assign the file to the new container.
there is no such notion as "rights to move a file to a new container".
The same file can be opened in processes belonging to other containers.
And you have no any clue whether to have to change the owner or not.

Though the point is, if a resource (like file) is getting migrated to a
new container then all the attributes (like owner, #pages in memory
etc.) attached to that resource (file) should also migrate to this new
container. Otherwise the semantics of where does the resource belong
becomes very difficult.
The same for many other resources. It is a big mistake thinking that most resources
belong to the processes and the owner process can be easily determined.

And if you really want a resource to not be able to migrate from one
container then we could define IMMUTABLE flag to indicate that behavior.
I hope not that one used in ext[23]? :)


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at