Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!lll-crg!mordor!sri-spam!nike!ucbcad!ucbvax!UWOCC1.BITNET!A105 From: A105@UWOCC1.BITNET (Brent Sterner) Newsgroups: mod.computers.vax Subject: VAX CPU usage not reproducible Message-ID: <8609201153.AA04249@ucbvax.Berkeley.EDU> Date: Fri, 19-Sep-86 11:55:00 EDT Article-I.D.: ucbvax.8609201153.AA04249 Posted: Fri Sep 19 11:55:00 1986 Date-Received: Sat, 20-Sep-86 20:42:29 EDT Sender: daemon@ucbvax.BERKELEY.EDU Organization: The ARPA Internet Lines: 27 Approved: info-vax@sri-kl.arpa Help again. It has been brought to my attention here that a user running a fixed job can be charged varying amounts. Our charging algorithm is simply rate/hour times CPU used. This means that a user performing the same task repeatedly with identical data is using differing amounts of CPU resource. For our site, this is not good. My impression is that some (perhaps all?) system overhead is being tallied against user jobs. Is this so? Is there any way to stop this happening? For our site, reproducibility (ie fairness) is important. One of the factors which specifically seems to be at fault is paging. As available memory saturates, and paging increases, the individual job costs rise. There may be other components affecting us as well. If there is no way to remove system overhead from our cost calculations, has anyone investigated ways of estimating it (based on paging for the job and/or other factors)? If so, the estimated overhead could be applied to the cost calculations to reduce the impact of the overhead. I'm open to any/all suggestions. Please reply direct to me, and if interest is sufficient I'll summarize to the net. Thanks in advance. Brent Sterner Computing & Communications Services Natural Sciences Building The University of Western Ontario London, Ontario, Canada N6A 5B7 Telephone (519)661-2151 x6036 Network