home *** CD-ROM | disk | FTP | other *** search
- Path: sparky!uunet!stanford.edu!agate!spool.mu.edu!howland.reston.ans.net!sol.ctr.columbia.edu!hamblin.math.byu.edu!arizona.edu!mvb.saic.com!macro32
- Newsgroups: vmsnet.internals
- Subject: Re: How to force a process into one CPU on a 6640?
- Message-ID: <8C41AD70BA9F23FF7A@MAX.U.WASHINGTON.EDU>
- From: DEREK@U.WASHINGTON.EDU
- Date: Wed, 27 Jan 93 11:26 PST
- Organization: Macro32<==>Vmsnet.Internals Gateway
- X-Gateway-Source-Info: Mailing List
- Lines: 46
-
- Tom O'Toole (ecf_stbo@jhuvms.hcf.jhu.edu) writes:
-
- >Pekka.Savolainen@Salcom.Fi writes...
- >>Included, please find sys$examples:bind_read_me.txt
- >
- >I'm curious if anyone has explored the license implications of this.
-
- YES! We have. Now, although I haven't looked in the solution provided by
- Pekka, I did look into this technology quite a lot back in earlier versions
- of VMS (T5.2 and some before this.) My thought was to be able to restrict
- CPU-hogging batch jobs to a subset of the available CPUs, thus providing
- better response time to the interactive users. (See, we could raise QUANTUM
- up (good for a vector CPU) and not feel the effects of multiple batch jobs
- so much.) Anyway, VMS Engineering kept changing the scheduler on me, so
- we waited until the activity died down. (At one point, I was given
- information on how to call a system routine to restrict a process to a
- CPU. It only crashed the system. I didn't use that routine after that.) :)
-
- Now that this seems fairly stable (we are at V5.5-1), we are using this to
- our advantage. Specifically, we had an 6000-420 which we wanted to upgrade
- to a 6000-440. The vendors of S1032 (I don't remember their name) wanted
- big bucks for a new license. We worked out a deal where we restrict the
- users of S1032 to a single CPU, and now we can move S1032 from (I believe)
- a 6000-420 up to a 6000-530 with no additional charge.
-
- How did we implement this? First, we restrict access to the S1032 files
- and images. In order to run S1032, you first invoke a set up procedure
- which: 1) raises your base priority to 5, 2) restricts you to a subset of
- the available CPUs, and 3) grants you the identifiers needed to run S1032.
-
- The priority 5 business help ensure that these users get scheduled "fairly".
- (Otherwise, they would only get to run 50% of the time. 2 out of 4 CPUs.)
- Since they can only run on 2 of the 4 CPUs, the priority 4 users don't feel
- much of an impact. Note: the non-S1032 users may be scheduled on ANY
- available CPU.
-
- Questions? Comments? Flames? Anyone read this far? :)
-
- -Derek S. Haining
- University Computing Services
- University of Washington
- Seattle, Washington 98195
- (206) 543-5579
-
- DEREK@MAX.BITNET
- DEREK@MAX.U.WASHINGTON.EDU
-