Next OSADL Events:
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Breaking News:
2010-02-08 12:00
Prof Eben Moglen on "GNU GPL Version 3: The Law Making Process"
International Conference on Commons, Users, Service Providers Internet (Self-)Regulation and Copyright
2009-11-23 12:00
Added a new HOWTO to the OSADL Website: Use BuildRoot to create a Linux image for QEMU
Guest Editor Bogdan Cristea tells us about rapid prototyping of an embedded system using virtualization
2009-11-19 12:00
Meet OSADL and many of its members at the SPS/IPC/Drives 2009
Open Source and Linux in Automation - the collaborative environment we always wished we had
2009-11-18 12:00
SERCOS III middleware library available as Open Source
Download the Common SERCOS Master API from the Internet
2009-10-21 12:00
Will we always wake up in time?
The Linux real-time kernel now contains a wakeup latency recorder to continuously monitor the real-time capabilities of a computer system |
OSADL Project: Realtime Linux
Is realtime possible with Linux? Yes, it is. But which Linux derivate should I use? This is the key question to be answered when Linux is going to be used in the automation industry.
The OSADL criteria for realtime Linux are:
- Strong and agile community
- Long term availability
- Ease of use (user space realtime)
- POSIX API for real time (standard API)
- Wide architecture support
- Mainstream support by the Vanilla Kernel
This project supports the evolution of the realtime preempt patch maintained by Ingo Molnar, and Thomas Gleixner. We believe that long term stability can only be achieved when the realtime aspects are as close to the Vanilla Kernel as possible.
Realtime Linux Road Map
This is the current status of Realtime Linux using the Realtime-Preempt patches:
Architecture | x86 | x86/64 | powerpc | arm | mips | 68knommu |
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Deterministic Scheduler |
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Preemption Support |
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PI Mutexes | |
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High-Resolution Timer |
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Preemptive Read-Copy Update |
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IRQ Threads |
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Raw Spinlock Annotation |
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Full Realtime Preemption Support |
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Available in mainline Linux
Available when Realtime-Preempt patches applied
1) Since kernel 2.6.24 in mainline Linux
2) Since kernel 2.6.25 in mainline Linux
3) Realtime-Preempt patches 2.6.24.7-rt15 or higher required
4) Since kernel 2.6.30 in mainline Linux
5) Not yet adapted to generic interrupt code
6) Merged for mainline Linux 2.6.33
Download Locations of Realtime Linux
- The Linux Kernel: Linux Vanilla Kernel
- The Real Time Preempt Patch: RT Preempt Download Page at kernel.org
"Latest stable" Realtime Linux
Kernel
www.kernel.org/pub/linux/kernel/v2.6/linux-2.6.29.6.tar.bz2
RT-Preempt Patch
rt.et.redhat.com/download/patch-2.6.29.6-rt24.bz2
Realtime Linux Installation Instructions
Quick overview
A quick list of the commands needed to download, patch and build an RT-Preempt realtime Linux kernel is given 
here.
HOWTO
A more detailed description how to equip the Linux kernel wth realtime capabilities is given here.