NAME

       lat_mmap - costs of mmapping and unmmapping varying file sizes

SYNOPSIS

       lat_mmap [ -P <parallelism> ] [ -W <warmups> ] [ -N <repetitions> ] size file

DESCRIPTION

       lat_mmap  times  how  fast  a mapping can be made and unmade.  This is useful because it is a fundamental
       part of processes that use SunOS style shared libraries (the libraries are mapped in at process start  up
       time and unmapped at process exit).

       The benchmark maps in and unmaps the first size bytes of the file repeatedly and reports the average time
       for one mapping/unmapping.

       The size specification may end with ``k'' or ``m'' to mean kilobytes (* 1024)  or  megabytes  (*  1024  *
       1024).

OUTPUT

       Output format is "%0.2f %d\n", megabytes, usecs, i.e.,

       8.00 1200

ACKNOWLEDGEMENT

       Funding for the development of this tool was provided by Sun Microsystems Computer Corporation.

SEE ALSO

       lmbench(8).

AUTHOR

       Carl Staelin and Larry McVoy

       Comments, suggestions, and bug reports are always welcome.

(c)1994 Larry McVoy                                  $Date$                                          LAT_MMAP(8)