Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site utcs.uucp Path: utzoo!utcs!wagner From: wagner@utcs.uucp (Michael Wagner) Newsgroups: net.unix-wizards Subject: Re: 4.2bsd kernel auto-nicing, scheduling Message-ID: <1155@utcs.uucp> Date: Mon, 10-Mar-86 10:45:56 EST Article-I.D.: utcs.1155 Posted: Mon Mar 10 10:45:56 1986 Date-Received: Mon, 10-Mar-86 10:59:56 EST References: <1014@brl-smoke.ARPA> <856@inset.UUCP> <3311@sun.uucp> <172@epimass.UUCP> Reply-To: wagner@utcs.UUCP (Michael Wagner) Organization: University of Toronto Computing Services, general purpose UNIX Lines: 29 Keywords: Scheduler Algorithm Finiteness Termination Summary: Schedulers restored to the status of Algorithms (at least temporarily) In article <172@epimass.UUCP> jbuck@epimass.UUCP (Joe Buck) writes: >I don't believe it! I, a mere mortal, get to correct Guy Harris :-). I don't think so. At least not this time. >Though you frequently see the word "algorithm" associated with schedulers, >they are not because they don't terminate (at least they aren't supposed >to). I certainly think schedulers terminate. There might be some confusion about either what a scheduler is or what time scale to examine their behaviour on. Schedulers that I am familiar with are entered to decide who to run next, and return (i.e. terminate) with a recommendation. If it were otherwise, you'd never get any useful work done. The scheduler does, usually, keep some sort of historical data around to assist in it's decisions, but that doesn't change the fact that it doesn't run all the time. > >Of course, the function that decides the next process to be executed at >a given time is (I hope!) an algorithm. >-- >- Joe Buck The function that decides the next process to be executed at a given time is (I hope) a scheduler! Michael Wagner (wagner@utcs)