winscape 2375

Reliability in that one application can wedge the whole system requiring a reboot. Everything stops. Work in progress has to be re-done.

Scheduler decides which task to run next. Rudimentary job control is round-robin; when one task yields, the next one gets to use the machine until it yields control.

It need not be overly-complex. Indeed; systems with preemptive multi-tasking tend to have simpler application internals because they don't have to consider the presence of other applications; unless they want to co-operate with them.

The speed of light is pretty damned quick.

And I said 100 milliseconds; i.e. one tenth of a second. If you're typing on screen and not using some obnoxious software that's trained you otherwise; or over a slow remote link imposing echo delays; then 0.1 seconds between keypress and the letter appearing on-screen is quite tardy.

It's equivalent to less having less than a 300 bps dialup link.

If the mouse pointer doesn't continuously follow where the system thinks that the user is pointing, then they will inevitably click on the button confirming thermo-nuclear detonation -- or something approximately the same. UI events aren't even time-stamped so the popup that steals focus will get the mouse click... so instead of sending an email; you launch an ICBM.

Real time requires that the system respond within a pre-defined period of time. That's not something that I've ever seen happen on MicroSnot's Windows. Not even with enough CPU clock frequency to make a microwave oven envious.

100 millisecond response is pretty slack in terms of UI handling. Quite lazy.

Humans tend to have a "worry reflex" that's triggered when the computer doesn't respond to their input within about 3 seconds. So they press the button again; or if using a PC, will press CTRL-ALT-DEL. -- "Bernd Felsche - Innovative Reckoning, Perth, Western Australia ASCII ribbon campaign PoliticianPol`i*ti"cian-, n. X against HTML mail One with a permanent smile and postings on both his faces