Cyclic Scheduling for linux

Cyclic Scheduling for linux

[First Name]

Hi there,

I am working on providing a cyclic scheduling policy
to the current non real time version of the linux to
support hard real time tasks as part of one of my
projects. This policy should be able to support
aperiodic, periodic and sporadic tasks too. Could any
one pour some light on how to go about achieving it?.

Any Helpful tips, project reports, links or advices
are greatly appreciated.

Thanks and Regards,
LQ

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Re: Cyclic Scheduling for linux

[George Anzinger]

First Name wrote:
> Hi there,
> 
> I am working on providing a cyclic scheduling policy
> to the current non real time version of the linux to
> support hard real time tasks as part of one of my
> projects. This policy should be able to support
> aperiodic, periodic and sporadic tasks too. Could any
> one pour some light on how to go about achieving it?.
> 
> Any Helpful tips, project reports, links or advices
> are greatly appreciated.

Instead of kernel changes, you might want to consider a user monitor task 
running at high rt priority which changes the priority of the tasks you want to 
use the new policy.  You could write an intercept routine for the scheduleset* 
calls and pass the new policy to the monitor.  More thought would be needed to 
make it inherit across a fork..

-g
> 
> Thanks and Regards,
> LQ
> 
> __________________________________
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-- 
George Anzinger   george@mvista.com
High-res-timers:  http://sourceforge.net/projects/high-res-timers/
Preemption patch: http://www.kernel.org/pub/linux/kernel/people/rml

Re: Cyclic Scheduling for linux

[George Anzinger]

He is supposed to do this for a class.  I wonder if the teacher would give extra 
credits for grabbing on open source solution instead of writting the code...

But then you did not say the Concurrent thing was open source. :)

-g

Albert Cahalan wrote:
>>I am working on providing a cyclic scheduling policy
>>to the current non real time version of the linux to
>>support hard real time tasks as part of one of my
>>projects. This policy should be able to support
>>aperiodic, periodic and sporadic tasks too. Could any
>>one pour some light on how to go about achieving it?.
>>
>>Any Helpful tips, project reports, links or advices
>>are greatly appreciated.
> 
> 
> I suppose you expect to write this, but if not,
> you can get it in Concurrent's Red Hawk Linux
> product.
> 
> Marketing says:
> 
> "RedHawk's Frequency-Based Scheduler (FBS) is a
> high-resolution task scheduler that enables the
> user to run processes in cyclical execution patterns.
> FBS can control the periodic execution of multiple,
> coordinated processes utilizing major and minor
> cycles with overrun detection. A performance
> monitor is also provided to view CPU utilization
> during each scheduled execution frame."
> 
> That's on a "real" Linux kernel, not like RTAI
> or RT-Linux. There are some other cool real-time
> features as well, and an Ada compiler if you're
> so inclined.
> 
> 
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 

-- 
George Anzinger   george@mvista.com
High-res-timers:  http://sourceforge.net/projects/high-res-timers/
Preemption patch: http://www.kernel.org/pub/linux/kernel/people/rml

Cyclic Scheduling for linux

[Albert Cahalan]

> I am working on providing a cyclic scheduling policy
> to the current non real time version of the linux to
> support hard real time tasks as part of one of my
> projects. This policy should be able to support
> aperiodic, periodic and sporadic tasks too. Could any
> one pour some light on how to go about achieving it?.
>
> Any Helpful tips, project reports, links or advices
> are greatly appreciated.

I suppose you expect to write this, but if not,
you can get it in Concurrent's Red Hawk Linux
product.

Marketing says:

"RedHawk's Frequency-Based Scheduler (FBS) is a
high-resolution task scheduler that enables the
user to run processes in cyclical execution patterns.
FBS can control the periodic execution of multiple,
coordinated processes utilizing major and minor
cycles with overrun detection. A performance
monitor is also provided to view CPU utilization
during each scheduled execution frame."

That's on a "real" Linux kernel, not like RTAI
or RT-Linux. There are some other cool real-time
features as well, and an Ada compiler if you're
so inclined.