chris@yarra.oz.au (Chris Jankowski) (11/09/89)
In article <178@saucer.cs.utexas.edu> mok@cs.utexas.edu (Al Mok) writes: > * Time is an essential synchronization mechanism for solving certain > task coordination problems. An example is the Byzantine Generals problem > for which it has been proven that there is no asynchronous solution. > However, a solution is possible if the generals adopt the synchronous > protocol of voting in rounds. Each round of voting imposes a timing > constraint on the good generals. Could somebody define the problem, please? Looks interesting. > Having said all of the above, let me give you an academic definition > of a real-time system which does not have "time" in it: a real-time system > is one that must synchronize with processes whose progress it cannot > directly control. But how do you define "synchronise"? And has the verb got nothing to do with time (:-))? It is a nice definition anyway. The whole discussion seems to be now drifting into the following direction: How do we cope with the time constraints? Two approaches were often used: a cyclic scheduler a fixed priority run-to-completion scheduler Obviously for a particular class of problems one may be better then the other. But are they general enough? Do we use them because we do not know or care to use something better? -m------- Chris Jankowski - Senior Systems Engineer chris@yarra.oz{.au} ---mmm----- Pyramid Technology Corporation Pty. Ltd. fax +61 3 820 0536 -----mmmmm--- 11th Floor, 14 Queens Road tel. +61 3 820 0711 -------mmmmmmm- Melbourne, Victoria, 3004 AUSTRALIA (03) 820 0711 Communism (East Germany) - versus - Capitalism (West Germany) 15,000 East Germans ->...short trip...-> 15,000 West Germans repeat each day