About consuming time slice on l4linux

Adam Lackorzynski adam at os.inf.tu-dresden.de
Mon May 17 22:38:54 CEST 2010

On Thu May 13, 2010 at 13:03:44 +0900, Jungwoo Yang wrote:
> I know that l4linux cpu always is allocated on 4th thread on linux server.
> Also, I want to assign specific timeslice into the linux CPU thread to
> operate its linux kernel and its user task.
> To do this, I wanted to be expected in one of linux can use CPU more
> than another linux. However, even though I assigned timeslice more (it
> can be done by adding schedule context), 2 linux servers is seemed to
> be using almost same the amount of CPU. I think that this is because
> of idle thread. If idle thread is executed, other linux can preempt
> the linux. Am I right?

In idle context the thread should idle, i.e. sleep and not consume CPU.
So if any other thread in the system is ready it will be scheduled.
Calling that 'can preempt' is a bit strange though as when a thread goes
to sleep it does this itself.

> also, I'm wondering whether user task consumes their own timeslice or
> donated timeslice from CPU thread.

No donation is done.

Adam                 adam at os.inf.tu-dresden.de
  Lackorzynski         http://os.inf.tu-dresden.de/~adam/

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