<!-- Copyright (c) 2000, 2001, 2002, 2003, 2004, 2005, 2008, 2009, 2013 The President and Fellows of Harvard College. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. Neither the name of the University nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE UNIVERSITY AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE UNIVERSITY OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. --> <html> <head> <title>parallelvm</title> <body bgcolor=#ffffff> <h2 align=center>parallelvm</h2> <h4 align=center>OS/161 Reference Manual</h4> <h3>Name</h3> <p> parallelvm - concurrent VM system test </p> <h3>Synopsis</h3> <p> <tt>/testbin/parallelvm</tt> </p> <h3>Description</h3> <p> <tt>parallelvm</tt> runs a fairly large number (24) of fairly small processes in parallel to stress your VM system. The processes perform aimless matrix operations. </p> <p> Before attempting <tt>parallevm</tt> make sure the <tt>zero</tt> test passes; <tt>parallelvm</tt> will fail with wrong answers if its BSS doesn't start out zeroed. Also, it may be helpful to get it running successfully purely in RAM before cutting back the memory size so it swaps. </p> <p> If your VM system's fork is particularly slow, you will probably find that the early processes exit before the later ones finish forking. This reduces the total memory load and can easily cause <tt>parallelvm</tt> to run completely in RAM without needing to swap; this in turn makes it a much less effective stress test. The only real remedy for this (other than making your fork faster) is to make each subprocess run longer; this currently requires patching the test. </p> <h3>Requirements</h3> <p> <tt>parallelvm</tt> uses the following system calls: <ul> <li> <A HREF=../syscall/getpid.html>getpid</A> <li> <A HREF=../syscall/fork.html>fork</A> <li> <A HREF=../syscall/fork.html>waitpid</A> <li> <A HREF=../syscall/write.html>write</A> <li> <A HREF=../syscall/_exit.html>_exit</A> </ul> </p> <p> <tt>parallelvm</tt> should run properly once your VM system is complete. </p> </body> </html>