Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!mailrus!umich!umeecs!walden@dip.eecs.umich.edu From: walden@dip.eecs.umich.edu (Eugene Marvin Walden) Newsgroups: comp.realtime Subject: Survey of Commercial Real-Time Operating Systems II Message-ID: <3036@zipeecs.umich.edu> Date: 10 Aug 90 15:31:37 GMT Sender: news@zip.eecs.umich.edu Organization: University of Michigan EECS Dept, Ann Arbor, MI Lines: 304 Well, folks, this is part II of my summary of commercial real-time operating systems. I was able to find most of the addresses, but, as you can see, six are still missing. Anyway, if anybody has corrections or further additions, please E-mail me. I have tried to provide a rough classification of the RTOSs that I have seen. The classifications may be inaccurate, or just plain wrong, but I tried. After I receive literature from these companies, maybe I'll post a summary of each OS. Have fun! 1. Regulus Alcyon Corp. 6888 Nancy Ridge Dr. San Diego, CA. 92121 (619) 587-1155 - UNIX-like operating system with real-time extensions 2. REAL/IX Modcomp John Worden 1650 W. McNab Rd. Ft. Lauderdale, FL 33340-6099 (305) 977-1083 - UNIX-like operating system with real-time extensions 3. CX/RT Harris Computer Systems Division 2101 W. Cypress Creek Rd. Ft. Lauderdale, FL. (305) 974-1700 - UNIX-like operating system with real-time extensions - Scheduler is a combination of a deadline-driven scheduler and a multi- level round-robin scheduler 4. Chimera II Carnegie-Mellon University - UNIX-like operating system with real-time extensions 5. LynxOS Lynx Real-Time Systems, Inc. 550 Division St. Campbell, CA. 95008 (408) 370-2233 - UNIX-like operating system with real-time extensions 6. FlexOS Digital Research, Inc. Integrated Systems Business Unit 70 Garden Court, B206 Monterey, CA 93940 (408) 982-0700 - UNIX-like operating system with real-time extensions 7. RTE Hewlett-Packard 8. pSOS Software Components Group 1731 Technology Dr. San Jose, CA 95110 (408) 437-0700 - UNIX-compatible kernel, < 12K 9. MTOS (Industrial Programming, Inc.) 10. PDOS (Eyering Research) 11. C Executive JMI Software Consultants 904 Sheble Ln. P.O. Box 481 Spring House, PA 19477 (215) 628-0846 12. RTUX Emerge Systems Frank Aaron 114 6th Ave., P.O. Box 3175 Indialantic, FL 32903 (407) 723-0444 - UNIX-like operating system with real-time extensions 13. CSX (Cytek) 14. AMX (Kadak) Kadak Products, Ltd. 206-1847 West Broadway Vancouver, BC Canada V6J 1Y5 (604) 734-2796 15. UniFlex UniFLEX Computing, Ltd. 111 Providence Rd. Chapel Hill, NC 27514 (919) 493-1451 Sales: (800) 486-1000 16. IDRIS (Whitesmiths) - UNIX-like operating system with real-time extensions 17. RTXC A. T. Barrett & Assoc. Ron Hodge 11501 Chimney Rock, Suite R Houston, TX 77035 18. USX US Software John Bayer 14215 NW Science Park Dr. Portland, OR 97229 (503) 641-8446 19. UMAX V OS Encore Computer Corp. 6901 W. Sunrise Blvd. Ft. Lauderdale, FL 33313 (305) 587-2900 - UNIX-like operating system with real-time extensions 20. VRTX Ready Systems 470 Potrero Ave. P.O. Box 60217 Sunnyvale, CA 94088-0217 (800) 228-1249 - small, ROMable kernel - priority-based round-robin scheduler - message passing, interrupt handling, semaphores 21. VxWorks Wind River Systems 1351 Ocean Ave. Emeryville, CA 94608 (415) 428-2623 - small, ROMable kernel - priority-based round-robin scheduler - message passing, interrupt handling, semaphores 22. iRMX and Distributed iRMX Intel Corp. 5200 N.E. Elam Young Pkwy. M.S. HF3-58 Hillsboro, OR 97124 (503) 681-8080 - small, ROMable kernel - priority-based round-robin scheduler - message passing, interrupt handling, semaphores 23. QNX Quantum Software Systems, Ltd. 175 Terrence Matthews Crescent Kanata, Ontario Canada K2M 1W8 (613) 591-0931 - like UNIX, but different enough to annoy the hell out of you - priority-based round-robin scheduler - message passing, interrupt handling, semaphore locking 24. Alpha Concurrent Computer Corp. One Technology Way Westford, MA 01886 (508) 692-6200 - two-dimensional priority specification - real-time transactions - object-oriented structure - 25. OS9, OS9000 Microware 1900 N.W. 114th St. Des Moines, Iowa 50322 (515) 224-1929 26. RTU Concurrent Computer Corp. One Technology Way Westford, MA 01886 (508) 692-6200 27. RT-11 Digital Equipment Corp. Class 1: The oldest "real-time" operating systems are systems that were used back in the Dark Ages such as Hewlett-Packerd's RTE and DEC's RT-11. Keep in mind that I never had to use the dreaded punch cards, so Dark Ages to me means early eighties :-). Class 2: The second generation of "real-time" operating systems were the real-time executives that were used for embedded data acquisition & control. These exec- utives typically handle message-passing primitives, simple task scheduling according to priority, semaphores and queues. They are usually fairly small, the main purpose being to provide an interface to a single-board computer. Ex- amples of such real-time operating systems are: - VRTX - iRMX - VxWorks - AMX - C-Executive Class 3: With the rebirth of UNIX in the eighties, there also came an entourage of companies trying to retro-fit UNIX for real-time applications. Usually, the modifications include: - Fully preemptive, priority-based schedulers - Ability to lock tasks in memory (i.e. no page-faults for critical tasks) - Faster context switches - Lower interrupt latency - Higher granularity Examples include: - Regulus - REAL/IX - LynxOS - FlexOS - pSOS - RTUX - QNX - Idris Class 4: This class is closely related to Class 3 above. More companies are introduc- ing multiprocessor machines, and with these machines come new operating sys- tems. All such systems I have seen are some form of UNIX, but extended to handle multiprocessing and real-time. Examples include: - CX/RT - UMAX V OS - RTU Class 5: I am biased towards the RTOSs with the academically interesting schedulers, but currently, there are not many. Some of the UNIX-like RTOSs are working on schedulers other than priority-based schedulers. 1. Alpha has a modular scheduler. Policy modules can be inserted into the scheduling scheme, so Alpha itself does not dictate the scheduling pol- icy. I believe that the available scheduling policies are simple priority based schedulers, deadline-driven schedulers, and possibly the Best Effort Scheduler. 2. LynxOS is developing a deadline-driven scheduler for the NASA Space Station. 3. CX/RT uses some combination of a deadline-driven scheduler and a multi- level round robin scheduler. 4. Chimera-II uses a least-laxity scheduler There you have it. If anybody wants to send me info, my mailing address is: Eugene Walden University of Michigan Space Physics Research Lab 2455 Hayward St. Ann Arbor, MI. 48109 (313) 764-0137 walden@dip.eecs.umich.edu