iotop(1m) [mojave man page]

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

NAME

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

SYNOPSIS

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

DESCRIPTION

       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 command.

OPTIONS

       -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

EXAMPLES

       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

FIELDS

       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

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

       DISKTIME
	      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

DOCUMENTATION

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

EXIT

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

AUTHOR

       Brendan Gregg [Sydney, Australia]

SEE ALSO

       iosnoop(1M), dtrace(1M)

version 0.75							   Oct 25, 2005 							 iotop(1m)

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procsystime(1m) 						   USER COMMANDS						   procsystime(1m)

NAME

       procsystime - analyse system call times. Uses DTrace.

SYNOPSIS

       procsystime [-acehoT] [ -p PID | -n name | command ]

DESCRIPTION

       procsystime prints details on system call times for processes, both the elapsed times and on-cpu times can be printed.

       The elapsed times are interesting, to help identify syscalls that take some time to complete (during which the process may have slept). CPU
       time helps us identify syscalls that are consuming CPU cycles to run.

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

OPTIONS

       -a     print all data

       -c     print syscall counts

       -e     print elapsed times, ns

       -o     print CPU times, ns

       -T     print totals

       -p PID examine this PID

       -n name
	      examine processes which have this name

EXAMPLES

       Print elapsed times for PID 1871,
	      # procsystime -p 1871

       Print elapsed times for processes called "tar",
	      # procsystime -n tar

       Print CPU times for "tar" processes,
	      # procsystime -on tar

       Print syscall counts for "tar" processes,
	      # procsystime -cn tar

       Print elapsed and CPU times for "tar" processes,
	      # procsystime -eon tar

       print all details for "bash" processes,
	      # procsystime -aTn bash

       run and print details for "df -h",
	      # procsystime df -h

FIELDS

       SYSCALL
	      System call name

       TIME (ns)
	      Total time, nanoseconds

       COUNT  Number of occurrences

DOCUMENTATION

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

EXIT

       procsystime will sample until Ctrl-C is hit.

AUTHOR

       Brendan Gregg [Sydney, Australia]

SEE ALSO

       dtruss(1M), dtrace(1M), truss(1)

version 1.00							   Sep 22, 2005 						   procsystime(1m)

Linux and UNIX Man Pages

iotop(1m) [mojave man page]

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