NAME

       blkiomon - monitor block device I/O based o blktrace data

SYNOPSIS

       blkiomon  -I  interval  [  -h file ] [ -b file ] [ -d file ] [ -D file ] [ -Q path_name -q
       msg_queue_id -m msg_id ] [ -V ]

DESCRIPTION

       blkiomon is a block device I/O monitor. It periodically generates per-device request  size
       and  request latency statistics from blktrace data. It provides histograms as well as data
       that can be used to calculate min,  max,  average  and  variance.  For  this  purpose,  it
       consumes  D  and  C  traces  read  from  stdin.   Note, that this doesn't work for logical
       volumes, as high-level drivers don't see the completion of the events (C).

       There are options for binary output and human-readable output to files and stdout.  Output
       to a message queue is supported as well.

       There  is  no  need to use blkparse with blkiomon. blkiomon is capable of consuming binary
       output written to stdout by blktrace.

OPTIONS

       -I interval
       --interval=interval
              Set sample interval

       -h file
       --human-readable=file
              Human-readable output file. Use '-' for stdout.

       -b file
       --binary=file
              Binary output file. Use '-' for stdout.

       -d file
       --dump-lldd=file
              Output file for data emitted by low level device driver.

       -D file
       --debug=file
              Output file for debugging data. Use '-' for stdout.

       -Q path_name
       --msg-queue=path_name
              Sets path_name as path name for existing  message  queue  to  be  used  for  binary
              output.

       -q msg_queue_id
       --msg-queue-id=msg_queue_id
              Sets msg_queue_id as ID for an existing message queue to be used for binary output.

       -m msg_id
       --msg-id=msg_id
              Sets  msg_id as message identifier to be used for binary output messages written to
              an existing message queue.

       -V
       --version
              Print program version.

EXAMPLES

       To get I/O statistics for /dev/sdw every 10 seconds for a period  of  one  hour,  use  the
       following command:

           % blktrace /dev/sdw -a issue -a complete -w 3600 -o - | blkiomon -I 10 -h -

AUTHORS

       blkiomon and this man page were written by Martin Peschke.

REPORTING BUGS

       Report bugs to <linux-btrace@vger.kernel.org>

COPYRIGHT

       Copyright © 2008 IBM Corp.
       This  is  free  software.   You  may  redistribute copies of it under the terms of the GNU
       General Public License <http://www.gnu.org/licenses/gpl.html>.  There is NO  WARRANTY,  to
       the extent permitted by law.

SEE ALSO

       btrace (8), blktrace (8), blkparse (1), verify_blkparse (1), blkrawverify (1), btt (1)

                                          July 17, 2008                               BLKIOMON(8)