ChronOS Real-time Linux

ChronOS is a real-time Linux patch created by the Systems Software Research Group at Virginia Tech. It builds upon the CONFIG_PREEMPT_RT patch and is designed to provide a Linux kernel testbed for real-time scheduling and resource management research on multicore platforms. It also supports distributed real-time scheduling and resource management.

The current stable version of ChronOS is ChronOS 3.0 which is based on Linux kernel 3.0.24 and the CONFIG_PREEMPT_RT patch.

Try out our new beta version of ChronOS ChronOS 4.16 which is based on Linux kernel 4.16.8.

Installation Guide

To download ChronOS Linux, please refer to Downloading ChronOS Linux

For installation instructions, please refer to the Installation Guide.

For common installation problems and their solutions, please refer to Common Installation Problems.

Try out our new beta version! Downloading ChronOS Linux v3.4 and Installation Guide 3.4.

ChronOS v4.16 beta is out! Downloading ChronOS Linux v4.16 and Installation Guide 4.16

Documentation

• For architecture details, please see About ChronOS Linux
• For more information about distributed threads on ChronOS, please see ChronOS Distributed Threads.
• For documentation of the user-space APIs provided by ChronOS, please look at ChronOS Userspace Docs.
• For kernel programming tips and other related documentation, please look at Kernel Programming Tips

Getting the Code

In addition to the packages made available on our downloads page, the ChronOS source code is available in the form of git repositories, available here.

Publications

• An Experimental Evaluation of the Scalability of Real-Time Scheduling Algorithms on Large-Scale Multicore Platforms, Matthew Dellinger, Aaron Lindsay, and Binoy Ravindran, ACM Journal on Experimental Algorithmics, 2012, ©ACM, 2012. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution.

• Quantitative Evaluation of Single and Multicore Real-Time DVFS Schedulers in Linux, A. Barbalace and B. Ravindran, Technical Report, April 2012

• An Experimental Evaluation of Real-Time DVFS Scheduling Algorithms, S. Saha and B. Ravindran, 5th Annual International Systems and Storage Conference (SYSTOR), June 2012

• STM Concurrency Control for Embedded Real-Time Software with Tighter Time Bounds, M. El-Shambakey and B. Ravindran, ACM Design Automation Conference (DAC), June 2012 (full version of the paper is available as a Technical Report)

• Implementing Distributable Real-Time Threads in the Linux Kernel: Programming Interface and Scheduling Support, S. Fahmy, B. Ravindran, and E. D. Jensen, ACM Symposium on Applied Computing, Track on Operating Systems, March 2012, to appear.

• An Experimental Evaluation of Real-Time DVFS Scheduling Algorithms, Sonal Saha, MS Thesis, September 2011

• An Experimental Evaluation of the Scalability of Real-Time Scheduling Algorithms on Large-Scale Multicore Platforms, Matthew Dellinger, MS Thesis, April 2011

• ChronOS Linux: A Best-Effort Real-Time Multiprocessor Linux Kernel, Matthew Dellinger, Piyush Garyali, and Binoy Ravindran, ACM Design and Automation Conference (DAC 2011), June 2011, To appear. ©ACM, 2011. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution.

• On Best-Effort Utility Accrual Real-Time Scheduling on Multiprocessors, Piyush Garyali, Matthew Dellinger, and Binoy Ravindran, International Conference On Principles Of Distributed Systems (OPODIS 2010), December 2010

• On Best-Effort Utility Accrual Real-Time Scheduling on Multiprocessors, Piyush Garyali, MS Thesis, July 2010

• Collaborative Scheduling and Synchronization of Distributable Real-Time Threads, Sherif F. Fahmy, PhD Dissertation, May 2010

Past publications on distributed threads and real-time scheduling are available here.

ChronOS News

Latest Development News

• Sep 30, 2018. We have upgraded ChronOS to Linux kernel 4.16. This implementation contains schedulers that do not use locking mechanisms and is released as ChronOS Beta 4.16 4.16. (We plan to release a 4.16 kernel version that contains lock-based schedulers in the near future.)
• July 06, 2015 - ChronOS Beta 3.4.1.
• April 18, 2014 - ChronOS Beta 3.4.
• April 16, 2012 - ChronOS RT-DVFS Pandaboard.
• March 20, 2012 - ChronOS 3.0. (Changelog).
• February 22, 2012 - ChronOS RT-DVFS Intel i5 and ChronOS RT-DVFS AMD Zacate.

Note that these ChronOS releases contain experimental implementations of RT-DVFS schedulers for the designated target processor.

• January 21, 2012 - ChronOS 3.0-rc1.
• October 28, 2011 - ChronOS Beta 2.8 Released. (Changelog).

Note that if you downloaded this release before November 4th, 2011, there was an error in the libchronos that shipped with the release, and you should re-download it to get the fixed version.

• April 12, 2011 - ChronOS Beta 2.7 Released. (Changelog).
• March 21, 2011 - ChronOS Beta 2.6 Released. (Changelog).
• Archived ChronOS Versions

Contact Information

IRC Channel

You can find us in the #chronoslinux channel on freenode.

Faculty Advisor

Binoy Ravindran binoy@vt.edu

Current Maintainer

• Ho-Ren(Jack) Chuang horenc@vt.edu

Other Developers

• Beichen Liu bcliu430@vt.edu

Past Contributors

• Antonio Barbalace antoniob@vt.edu
• Vincent Legout vlegout@vt.edu
• Kevin Burns kevinpb@vt.edu (M.S., 2014)
• Andy Martin andymartin@vt.edu (B.S. 2012)
• Aaron Lindsay Aaron Lindsay aaron.lindsay@vt.edu (M.S. 2012)
• Sonal Saha saha.sonal@gmail.com (M.S., 2011)
• Matthew Dellinger matthew@mdelling.com (M.S., 2011)
• Jonathan Anderson andersoj@andersoj.org
• Piyush Garyali piyushg@vt.edu (M.S., 2010)
• Sherif Fahmy fahmy@vt.edu (PhD., 2010)
• Caleb Hopkins (B.S., 2009)
• Surry Shome (B.S., 2009)