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This is the FAQ for the gRMA project. If you have a question that's not here, please email me.

General Questions about RMA

1: What is Rate Monotonic Analysis (RMA)?
2: What do you mean by a real-time system?

Specific Questions about the gRMA program

3: What operating systems will the program work on?
4: How far along in the project?
5: Who is that guy on the main page?

Question 1: What is Rate Monotonic Analysis (RMA)?

Rate Monotonic Analysis (RMA) is a set of quantitative methods used to analyze the timing behavior of real-time systems. RMA can take a description of a system's composition and it's timing requirements and answer the question: "Will it always meet its deadlines?" More importantly, when the answer is no RMA can be used to investigate the cause of the missed deadlines and aid in their correction.

Rate Monotonic Analysis originated with Lui and Layland's paper "Scheduling Algorithms for Multi-Programming in a Hard Real-Time Environment" which appeared in the Journal of the Association for Computing Machinery in January of 1973. At first the theory dealt only with rate monotonic scheduling but in time it was developed to apply to many scheduling policies. Much of the work of taking RMA from academia into practice was done at the Software Engineering Institute at Carnegie Mellon University. A more extensive definition and bibliography is available here.

Also available - the historical review of RMA I wrote (this is in the distribution above, in doc/).

Question 2: What do you mean by a real-time system?

For my purposes a real-time system is a system for which correctness depends on timing behavior. Another way of putting it - in a real-time system, a missed deadline is a failure. Most computer systems have some manner of timing requirement, usually of the "should seem fast enough" variety, but a real-time system depends on meeting deadlines absolutely. Popular examples of real-time systems include medical systems and aircraft guidance systems. The FAQ for the comp.realtime Usenet group is good resource for general questions about real-time systems.

Question 3: What operating systems does gRMA work on?

gRMA was designed and tested on a GNU/Linux system, and it will certainly run there. I believe it should run unmodified on many other systems that support X-Windows and Perl/Tk. It may run under Microsoft Windows 9x/NT, but no promises!

Question 4: How far along is the project?

So far I have the data entry system working fully - you can enter tasks and resources. You can use a graphical editor to associate tasks with resources. The system saves and loads and all that jazz.

What of the analysis? Download the current release and find out - a lot works, and a lot doesn't.

Question 5: Who is that guy on the main page?

He's Don Van Vliet, otherwise known as Captain Beefheart. He's the "mascot" of the gRMA project - most of the coding was done listening to his many fantastic albums. Find out more about the good Captain at:
www.beefheart.com banner