Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!munnari.oz.au!brolga!lingua.cltr.uq.OZ.AU!root From: root@lingua.cltr.uq.OZ.AU (Hulk Hogan) Newsgroups: comp.arch Subject: Re: ~8-job "knee" in response curves on Suns (was Re: IBM RS6000) Message-ID: <1991Jan21.230631.9060@lingua.cltr.uq.OZ.AU> Date: 21 Jan 91 23:06:31 GMT References: <1991Jan10.214122.9506@news.arc.nasa.gov> <5257@auspex.auspex.com> <3956@skye.ed.ac.uk> <3964@skye.ed.ac.uk> <4972@lure.latrobe.edu.au> Organization: Centre for Language Teaching and Research, Uni of Queensland, AUSTRALIA. Lines: 117 CCHD@lure.latrobe.edu.au (Huw Davies - La Trobe University Computer Centre) writes: >In article <3964@skye.ed.ac.uk>, richard@aiai.ed.ac.uk (Richard Tobin) writes: >> In article <3956@skye.ed.ac.uk> I wrote: >>>It forks n processes, which then write to each other in a circle of pipes. >>>Here are some results. >> Here are some more: >Here are (somewhat exhaustive results for a RS/6000-540 with 64Mb of >memory and no significant users). [...] >Procs: 1 - 306 switches / second >Procs: 2 - 2671 switches / second >Procs: 3 - 2391 switches / second >Procs: 4 - 1961 switches / second >Procs: 5 - 1939 switches / second [...] >Procs: 20 - 1964 switches / second [...] >Procs: 30 - 1947 switches / second [...] >Procs: 80 - 1795 switches / second [...] >Procs: 98 - 1742 switches / second >Procs: 99 - 27145 switches / second >Procs: 100 - 26898 switches / second >Procs: 101 - 27345 switches / second [...] Wow! Richard should sell his benchmark program to IBM or Intel! :-) Here's the results on a pretty idle Solbourne 5/601 in multiuser mode (33MHz SPARC, 16MB RAM, SunOS 4.0.3, Compiled with -O). The shell script I used is included for completeness after the results. There doesn't appear to be a knee that I can see. -------------------- cut here -------------------- Context Switch "knee" test. Machine: lingua. Architecture: sun4 Series5 Date: Tue Jan 22 08:43:55 EST 1991 Uptime: 8:43am up 22 mins, 1 user, load average: 1.24, 1.16, 0.80 N Output of knee N. 2 2857 switches / second 3 2308 switches / second 4 2222 switches / second 5 1852 switches / second 6 1875 switches / second 7 1667 switches / second 8 1778 switches / second 9 1698 switches / second 10 1667 switches / second 11 1507 switches / second 12 1818 switches / second 13 1970 switches / second 14 1867 switches / second 15 1667 switches / second 16 1839 switches / second 17 1868 switches / second 18 1782 switches / second 19 1520 switches / second 20 1653 switches / second 22 1618 switches / second 24 1509 switches / second 26 1793 switches / second 28 1795 switches / second 30 1657 switches / second 32 1975 switches / second 34 1659 switches / second 36 1706 switches / second 40 1762 switches / second 50 1534 switches / second 60 1579 switches / second 61 1690 switches / second 62 1562 switches / second 63 1507 switches / second 64 1693 switches / second 65 1693 switches / second 66 1692 switches / second 70 1493 switches / second 80 1572 switches / second Date: Tue Jan 22 08:45:09 EST 1991 Uptime: 8:45am up 23 mins, 1 user, load average: 15.20, 5.65, 2.72 -------------------- cut here -------------------- The shell script I used to run the benchmark was... -------------------- cut here -------------------- #!/bin/sh # run the knee benchmark cc -O -o knee knee.c echo "Context Switch \"knee\" test. Machine: `hostname`. Architecture: `arch` `arch -k`" > results echo "Date: `date`" >> results echo "Uptime: `uptime`" >> results echo >> results echo "N Output of knee N" for i in 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 22 24 26 28 30 32 34 36 40 50 60 61 62 63 64 65 66 70 80 do /bin/echo -n "$i " >> results knee $i >> results done echo >> results echo "Date: `date`" >> results echo "Uptime: `uptime`" >> results -------------------- cut here -------------------- /\ndy -- Andrew M. Jones, Systems Programmer, Internet: andy@lingua.cltr.uq.oz.au Centre for Lang. Teaching & Research, Phone (Australia): (07) 365 6915 University of Queensland, St. Lucia, Phone (World): +61 7 365 6915 Brisbane, Qld. AUSTRALIA 4072 Fax: +61 7 365 7077 "No matter what hits the fan, it's never distributed evenly....."