Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!milano!cadillac!vaughan@mcc.com From: vaughan@mcc.com (Paul Vaughan) Newsgroups: comp.lang.c++ Subject: Re: discrete-event simulation in C++ Message-ID: <10678@cadillac.CAD.MCC.COM> Date: 24 Aug 90 19:41:40 GMT References: <60862@lanl.gov> Sender: news@cadillac.CAD.MCC.COM Reply-To: vaughan@mcc.com (Paul Vaughan) Distribution: comp Organization: MCC VLSI CAD Program Lines: 22 In-reply-to: cimshop!davidm@uunet.UU.NET (David S. Masterson) Could someone please explain (briefly) what process oriented simulation is and contrast it to event oriented simulation? Something tells me I'll probably get it as soon as someone starts explaining it, but, right now, its meaning escapes me. Briefly, process base simulation allows simulation time to pass during the execution of a user-written function expressing simulation behavior. Functions such as wait(time), waitforevent(Event), etc., are provided in a library. That's why you need process switching capability to keep the context of several execution environments that are all at least conceptually concurrently executing. In a purely event based system all behavior functions are executed in zero simulation time. Events may be posted to cause things to happen at future times. All process based systems are essentially constructed out of event scheduling systems (it's all discrete event simulation, after all). Most process based libraries support the use of explicit events in addition to wait constructs. Paul Vaughan, MCC CAD Program | ARPA: vaughan@mcc.com | Phone: [512] 338-3639 Box 200195, Austin, TX 78720 | UUCP: ...!cs.utexas.edu!milano!cadillac!vaughan