Dedicated Systems have produced a report (not comissioned by Microsoft) that defines what Real-Time means for embedded systems, and compares three RTOS (Real-Time Operating Systems), this includes VxWorks, Montavista Linux, and Windows CE 5.0 - The following is an extract from the Dedicated Systems Web Site.

Dedicated Systems Experts, a company specializing in the verification and validation of real-time and embedded systems, announces the availability of a document "RTOS State of the ART - Understanding RTOS Technology and Markets".
This short document (24 pages) wants to introduce only the basic notions about real-time and especially RTOS and give a limited discussion about some products and markets.
In a first part real-time systems are defined in laymen´s terms. In a second part some commercial products such as VxWorks, Montavista Linux and Windows CE, are discussed in order to introduce in a pragmatic way some RTOS characteristics. The third part describes specific features that might be needed in some vertical markets such as Industrial Automation and Manufacturing, Medical Devices, Consumer Electronics, Retail and Automotive.

The report can be downloaded from
http://www.dedicated-systems.com/encyc/buyersguide/rtos/evaluations/docspreview.asp

One of the myths I've heard several times over the last few years is that Windows CE is not a hard real-time operating system, I would have to say that this report from Dedicated Systems, as well as the Dedicated Systems real-time analysis of Windows CE 5.0 based on x86 and ARM processors (documents here Windows CE 5.0 x86, Windows CE 5.0 ARM) would tend to show that Windows CE is a hard real-time operating system, and performs as well as VxWorks, and I very much doubt that anyone reading this blog post would consider VxWorks to not be a hard real-time operating system.

Summary of the paper is here... - Windows CE 5.0

  • “CE 5.0 exhibited real-time behavior during our tests.  None of the stress tests exposed any problems concerning stability and robustness either.”
  • “RT-VALIDATED”, CE 5.0 passed all tests without problems.”
  • “RTOS architecture 8/10- An appropriate architecture for an RTOS.”
  • “Test Results 7/10- What you would expect from a good RTOS.”
  • “Modular operating system, with a large amount of optional features. It can be extended with a lot of features such as a user interface, internet services and so on.”
  • “All protection primitives use priority inheritance! It is the only RTOS that we tested that exhibit this behavior. In our opinion all other RTOS should take an example on this. This will limit already the potential design flaws caused by incorrect usage of protection primitives.”
  • “Stable real-time results, worst case improved compared with CE 4.0.”

    Oh, and don't forget to listen to the Windows CE Real-Time Podcast interview with John Eldridge.

  • The Dedicated Systems report not only focuses on real-time but also examines other areas of the operating systems, and tools.

    Case Closed !

    - Mike