Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!rpi!crdgw1!crdos1!davidsen From: davidsen@crdos1.crd.ge.COM (Wm E Davidsen Jr) Newsgroups: comp.arch Subject: Re: How wrong is MS-DOS? (or: Tools Tools Tools) Message-ID: <3131@crdos1.crd.ge.COM> Date: 17 Jan 91 13:17:01 GMT References: <11255@lanl.gov> <1991Jan13.085556.1332@kithrup.COM> <3126@crdos1.crd.ge.COM> <2472@opal.cs.tu-berlin.de> Reply-To: davidsen@crdos1.crd.ge.com (bill davidsen) Organization: GE Corp R&D Center, Schenectady NY Lines: 31 In article <2472@opal.cs.tu-berlin.de> wg@opal.cs.tu-berlin.de writes: | davidsen@crdos1.crd.ge.COM (Wm E Davidsen Jr) writes: | | > My experience is that normally there is 1-5% CPU in the shell, leaving | >very little room for actual improvement. | | This is nosense, unless you measured process spawns and other system | services invoced by the shell. Did you? I pulled a section of the accounting file, and added up all the user and system cpu for all processes including the sh process. I called this the total. I then added the user and system cpu for the sh and called that the shell cpu. For three such jobs selected at random from scripts run from cron the shell cpu was from 1-5% of the total. Since then I did this for a few interractive shell scripts, and saw all numbers less than 10% for cpu used in shell. I'm not sure I undestand your question. I'm making a simple measurement, using the most easily available numbers. You are free to measure this any way you want and draw any conclusions you want. Obviously you can measure anything you want based on the cpu use of the processes started by the shell. In all cases the shell cpu was 1-3 sec, which gives some set of bounds on how much you could save by replacing the shell with a program. Pipe time is harder to eliminate, since each pipe means replacing two complete programs with one merged program. -- bill davidsen (davidsen@crdos1.crd.GE.COM -or- uunet!crdgw1!crdos1!davidsen) A system without MS-DOS compatibility is like a rock without mayonnaise