Article View: comp.sys.sgi.misc
Article #94Re: Where does the CPU go, when its not doing nuthin' (gr_osview)
From: Stephen J. Scotti
Date: Wed, 30 Dec 1992 17:35
Date: Wed, 30 Dec 1992 17:35
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1677 bytes
>| When looking at gr_osview, I have a program that uses about 50% of the >| cpu (indigo R4000 elan running 4.05F). The CPU wait line in gr_osview >| is empty, so if the cpu isn't waiting, why doesn't my program get 100% >| of the CPU? >| >| I guess the less naive way of putting this is: What factors aren't captured >| between the CPU Usage and CPU wait? >| >| [The program in question reads in a 16k chunks of stuff off of disk, messes >| around with them and writes them out. All to local disk.] >It's hard to say just where it is waiting. Running osview may be >helpful, as would 'timex -s yourprog'. My guess is that it is indeed >waiting for the disk part of the time. I have been running a structural analysis finite element code on a 4d35 with similar problems. I was the only user on the machine but could get no more than about 60% of the CPU. I too attributed this to disk accesses but when we upgraded our memory from 16mb to 48mb, I found that I could get about 95% of the CPU! I wonder if Dave Olson could explain that? Stephen J. Scotti ASB, NASA Langley Research Center s.j.scotti@larc.nasa.gov
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Path: arc1-ca.pugleaf.net!sparky!uunet!news.larc.nasa.gov!news From: s.j.scotti@larc.nasa.gov (Stephen J. Scotti) Newsgroups: comp.sys.sgi.misc Subject: Re: Where does the CPU go, when its not doing nuthin' (gr_osview) Date: 30 Dec 1992 17:35:14 GMT Organization: Aircraft Structures Branch, NASA Langley Research Center Lines: 26 Distribution: world Message-ID: <1hsmkiINNf05@rave.larc.nasa.gov> References: <to01eas@zuni.esd.sgi.com> Reply-To: s.j.scotti@larc.nasa.gov (Stephen J. Scotti) NNTP-Posting-Host: scotti.larc.nasa.gov