shmx(8) 						      System Manager's Manual							   shmx(8)

Name
       shmx - shared memory exerciser

Syntax
       /usr/field/shmx [ -h ] [ -ofile ] [ -ti ] [ -mj ] [ -sk ] [ -v ]

Description
       The  memory exerciser spawns a background process and these two processes exercise the shared memory segments. They each take turns writing
       and reading the other's data in the segments.

       You can specify the number of memory segments to test and the size of the segment to be tested by and processes. The exerciser  runs  until
       the process receives a or a kill -15 pid.

       A  logfile  is  made in for you to examine and then remove. If there are errors in the logfile, check the file, where the driver and kernel
       error messages are saved.  The exerciser is automatically invoked when the exerciser is started.  You can also run by itself.

Options
       -h	 Print the help message for the command.

       -v	 Use the system call instead of to spawn

       -ofile	 Save diagnostic output in file.

       -ti	 Run time in minutes (i).  The default is to run until the process receives a or a kill -15 pid.

       -mj	 The memory segment size in bytes (j) to be tested by the processes.  Must be greater than 0.  The default is SMMAX/6.	(SMMAX	is
		 a system parameter set in the file

       -sk	 The number of memory segments (k).  The default is 6.	The maximum is also 6.

Examples
       The following example tests six memory segments (default), each with a segment size of SMMAX/6, until a or kill -15 pid is received:
       % /usr/field/shmx
       The following example runs three memory segments of size 100,000 bytes for 180 minutes in the background:
       % /usr/field/shmx -t180 -m100000 -s3 &

Restrictions
       If  there  is  a  need to run a system exerciser over an NFS link or on a diskless system there are some restrictions.  For exercisers that
       need to write into a file system, such as the target file system must be writable by root.  Also the directory, in which any of	the  exer-
       cisers  are  executed,  must be writable by root because temporary files are written into the current directory.  These latter restrictions
       are sometimes difficult to overcome because often NFS file systems are mounted in a way that prevents root from writing into them.  Some of
       the restrictions may be overcome by copying the exerciser to another directory and then executing it.

See Also
       Guide to System Exercisers

																	   shmx(8)