Re: Real time scheduler C

DAC wrote:
If ANY of the processes running can take exclusive control of the system
locking out other processes then the response time of the system is NOT
guaranteed.

I don't really disagree with any of you guys im just saying that in some instances you can guarantee processes will not lock (since you coded them!).


It's (relatively) easy to be sure that your own self-written processes don't lock up, except of course if windows locks them during system calls. But you have no way of knowing what other processes are running. With a great deal of effort, you can limit a number of them, but you can't get them all. They are not specified in any way, and there is no available source code. Generally speaking, you don't even know who made them - typical windows systems are full of third-party code, even if it is stamped with Microsoft's name. There are processes running that don't show up on any lists such as task manager, and no way to control many of the tasks that do show up.

Windows can be a convenient platform for many uses, but you have *no* guarantees, and it cannot in any way be described as a real-time operating system. It might well be good enough for the job in hand, and it might be possible to provide empirical statistical evidence showing 99.99% timing correctness, but you have to be able to tolerate the 0.01% occasions when the OS decides that now would be a great time to defragment the hard disk.

If you want a reliable windows system with tight control over the running processes, you are better off with Windows 3.1.


.