iotop(1m)                         USER COMMANDS                        iotop(1m)

       iotop - display top disk I/O events by process. Uses DTrace.

       iotop [-C] [-D|-o|-P] [-j|-Z] [-d device] [-f filename] [-m mount_point]
       [-t top] [interval [count]]

       iotop tracks disk I/O by process, and prints a summary report that is
       refreshed every interval.

       This is measuring disk events that have made it past system caches.

       Since this uses DTrace, only users with root privileges can run this

       -C     don't clear the screen

       -D     print delta times - elapsed, us

       -j     print project ID

       -o     print disk delta times, us

       -P     print %I/O (disk delta times)

       -Z     print zone ID

       -d device
              instance name to snoop (eg, dad0)

       -f filename
              full pathname of file to snoop

       -m mount_point
              mountpoint for filesystem to snoop

       -t top print top number only

       Default output, print summary every 5 seconds
              # iotop

       One second samples,
              # iotop 1

       print %I/O (time based),
              # iotop -P

       Snoop events on the root filesystem only,
              # iotop -m /

       Print top 20 lines only,
              # iotop -t 20

       Print 12 x 5 second samples, scrolling,
              # iotop -C 5 12

       UID    user ID

       PID    process ID

       PPID   parent process ID

       PROJ   project ID

       ZONE   zone ID

       CMD    command name for the process

       DEVICE device name

       MAJ    device major number

       MIN    device minor number

       D      direction, Read or Write

       BYTES  total size of operations, bytes

              total elapsed times from request to completion, us (this is the
              elapsed time from the disk request (strategy) to the disk
              completion (iodone))

              total times for disk to complete request, us (this is the time for
              the disk to complete that event since it's last event (time
              between iodones), or, the time to the strategy if the disk had
              been idle)

       %I/O   percent disk I/O, based on time (DISKTIME)

       load   1 minute load average

       disk_r total disk read Kb for sample

       disk_w total disk write Kb for sample

       See the DTraceToolkit for further documentation under the Docs directory.
       The DTraceToolkit docs may include full worked examples with verbose
       descriptions explaining the output.

       iotop will run forever until Ctrl-C is hit, or the specified interval is

       Brendan Gregg [Sydney, Australia]

       iosnoop(1M), dtrace(1M)

version 0.75                    October 25, 2005                       iotop(1m)