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)