That link above has lots of good stuff! You might also take a look at
dedicated-systems (
http://www.dedicated-systems.com/), which is a
company that produces good test reports on RTOS capabilities. They
have a lot of stuff about Windows CE, and hard realtime in general.
Nothing about XPE though.
As for Safety Critical, I have not heard XPE discussed in connection
with safety critical much at all. There are many, many issues with
validating an entire OS! When I hear 'safety critical' I immediately
think of ISO/FDA and all of that, which require much documentation and
testing to certify product as safe. Are you contemplating putting XPE
into a medical device or military product or something like that??
I am aware of the CCEVT, the Common Criteria Evaluation and Validation
Scheme, which is an NIST/NSA website that is devoted to testing and
certifying IT projects as secure. This effort is directed at data
security, not at 'safety criticalness' If anyone is aware of a similar
effort that would 'validate' operating systems as stable and tested, I
would love to here about it.