[Bug 739] New: Xenomai scheduler setting is bogus

https://www.fmtc.be/bugzilla/orocos/show_bug.cgi?id=739

Summary: Xenomai scheduler setting is bogus
Product: RTT
Version: rtt-trunk
Platform: All
OS/Version: Xenomai 2.x
Status: NEW
Severity: normal
Priority: P3
Component: Operating System Abstraction - Portability
AssignedTo: orocos-dev [..] ...
ReportedBy: peter [..] ...
CC: orocos-dev [..] ...
Estimated Hours: 0.0

The current scheduler setting in Xenomai is implemented by forcing mode
switches, which is completely rediculous since Xenomai will switch us back to
the primary domain from the moment it has a chance.

The solution seems to be to map the scheduler settings to
SCHED_OTHER/SCHED_FIFO, just like in the gnulinux fosi. Once the thread is
running in SCHED_FIFO, it switches to the primary domain, otherwise it runs
with priority 0 in SCHED_OTHER.

I need to test this to figure out if this will actually work though.

Peter

[Bug 739] Xenomai scheduler setting is bogus

https://www.fmtc.be/bugzilla/orocos/show_bug.cgi?id=739

Peter Soetens <peter [..] ...> changed:

What |Removed |Added
----------------------------------------------------------------------------
Target Milestone|--- |next-bugfix
Resolution| |FIXED
Status|NEW |RESOLVED

--- Comment #3 from Peter Soetens <peter [..] ...> 2010-12-21 10:55:41 ---
We can Run Xenomai threads in sched_fifo with priority zero since RTT-1.12.0
without causing modeswitches. This requires Xenomai > 2.5.0

[Bug 739] Xenomai scheduler setting is bogus

https://www.fmtc.be/bugzilla/orocos/show_bug.cgi?id=739

--- Comment #2 from Peter Soetens <peter [..] ...> 2010-01-08 15:42:54 ---
(In reply to comment #1)
> (In reply to comment #0)
> > The current scheduler setting in Xenomai is implemented by forcing mode
> > switches, which is completely rediculous since Xenomai will switch us back to
> > the primary domain from the moment it has a chance.
> >
> > The solution seems to be to map the scheduler settings to
> > SCHED_OTHER/SCHED_FIFO, just like in the gnulinux fosi. Once the thread is
> > running in SCHED_FIFO, it switches to the primary domain, otherwise it runs
> > with priority 0 in SCHED_OTHER.
> >
> > I need to test this to figure out if this will actually work though.
>
> Any news on this one? (see
> <http://www.orocos.org/forum/orocos/orocos-users/new-110-activity-model-creates-useless-threads#comment-5544>

Not fixed yet in any branch. I don't have time yet for this.

Peter

[Bug 739] Xenomai scheduler setting is bogus

https://www.fmtc.be/bugzilla/orocos/show_bug.cgi?id=739

--- Comment #1 from Klaas Gadeyne <klaas [dot] gadeyne [..] ...> 2010-01-08 10:40:37 ---
(In reply to comment #0)
> The current scheduler setting in Xenomai is implemented by forcing mode
> switches, which is completely rediculous since Xenomai will switch us back to
> the primary domain from the moment it has a chance.
>
> The solution seems to be to map the scheduler settings to
> SCHED_OTHER/SCHED_FIFO, just like in the gnulinux fosi. Once the thread is
> running in SCHED_FIFO, it switches to the primary domain, otherwise it runs
> with priority 0 in SCHED_OTHER.
>
> I need to test this to figure out if this will actually work though.

Any news on this one? (see
<http://www.orocos.org/forum/orocos/orocos-users/new-110-activity-model-creates-useless-threads#comment-5544>