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LMDD(8)				    LMBENCH			       LMDD(8)

NAME
       lmdd - move io for performance and debugging tests

SYNOPSIS
       lmdd [ option=value ] ...

DESCRIPTION
       lmdd  copies a specified	input file to a	specified output with possible
       conversions.  This program is primarily useful for timing I/O since  it
       prints out the timing statistics	after completing.

OPTIONS
       if=name	      Input  file is taken from	name; internal is the default.
		      internal	is  a  special	file  that  acts  like	 Sun's
		      /dev/zero,  i.e.,	 it provides a buffer of zeros without
		      doing a system call to get them.
		      The following file names are taken to mean the  standard
		      input: -,	0, or stdin.

       of=name	      Output file is taken from	name; internal is the default.
		      internal is a special file  that	acts  like  /dev/null,
		      without doing a system call to get rid of	the data.
		      The  following file names	are taken to mean the standard
		      output: -, 1, or stdout.
		      The following file names are taken to mean the  standard
		      error: 2,	or stderr.

       bs=n	      Input  and  output  block	 size  n bytes (default	8192).
		      Note that	this is	different from dd(1),  it  has	a  512
		      byte  default.	Also  note  that the block size	can be
		      followed by 'k' or 'm' to	indicate kilo bytes (*1024) or
		      megabytes	(*1024*1024), respectively.

       ipat=n	      If  n  is	 non  zero, expect a known pattern in the file
		      (see opat).  Mismatches will  be	displayed  as  "ERROR:
		      off=%d  want=%x got=%x".	The pattern is a sequence of 4
		      byte integers with the first 0, second  1,  and  so  on.
		      The default is not to check for the pattern.

       opat=n	      If n is non zero,	generate a known pattern on the	output
		      stream.  Used for	 debugging  file  system  correctness.
		      The default is not to generate the pattern.

       mismatch=n     If  n  is	 non zero, stop	at the first mismatched	value.
		      Used with	ipat.

       skip=n	      Skip n input blocks before starting copy.

       fsync=n	      If n is non-zero,	call fsync(2) on the output  file  be-
		      fore exiting or printing timing statistics.

       sync=n	      If  n is non-zero, call sync(2) before exiting or	print-
		      ing timing statistics.

       rand=n	      This argument, by	default	off, turns on random behavior.
		      The  argument  is	not a flag, it is a size, that size is
		      used as the upper	bound for the seeks.  Also  note  that
		      the block	size can be followed by	'k' or 'm' to indicate
		      kilo bytes (*1024) or megabytes (*1024*1024),

       flush=n	      If n is non-zero and mmap(2) is available, call msync(2)
		      to invalidate the	output file.  This flushes the file to
		      disk so that you don't have unmount/mount.  It is	not as
		      good as mount/unmount because it just flushes file pages
		      -	it misses the indirect blocks which are	still  cached.
		      Not supported on all systems, compile time option.

       rusage=n	      If  n  is	 non-zero,  print rusage statistics as well as
		      timing statistics.  Not supported	on all	systems,  com-
		      pile time	option.

       count=n	      Copy only	n input	records.

EXAMPLES
       This  is	 the  most common usage, the intent is to measure disk perfor-
       mance.  The disk	is a spare partition mounted on	/spare.

	   # mount /spare
	   # lmdd if=internal of=/spare/XXX count=1000 fsync=1
	   7.81	MB in 3.78 seconds (2.0676 MB/sec)

	   : Flush cache
	   # umount /spare
	   # mount /spare

	   # lmdd if=/spare/XXX	of=internal
	   7.81	MB in 2.83 seconds (2.7611 MB/sec)

AUTHOR
       Larry McVoy, lm@sun.com

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

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | AUTHOR

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