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iopattern(1m) [osx man page]

iopattern(1m)							   USER COMMANDS						     iopattern(1m)

NAME

       iopattern - print disk I/O pattern. Uses DTrace.

SYNOPSIS

       iopattern [-v] [-d device] [-f filename] [-m mount_point] [interval [count]]

DESCRIPTION

       This  prints  details on the I/O access pattern for the disks, such as percentage of events that were of a random or sequential nature.	By
       default totals for all disks are printed.

       An event is considered random when the heads seek. This program prints the percentage of events that are random. The size of  the  seek	is
       not measured - it's either random or not.

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

OPTIONS

       -v     print timestamp, string

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

       -f filename
	      full pathname of file to snoop

       -m mount_point
	      mountpoint for filesystem to snoop

EXAMPLES

       Default output, print I/O summary every 1 second,
	      # iopattern

       Print 10 second samples,
	      # iopattern 10

       Print 12 x 5 second samples,
	      # iopattern 5 12

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

FIELDS

       %RAN   percentage of events of a random nature

       %SEQ   percentage of events of a sequential nature

       COUNT  number of I/O events

       MIN    minimum I/O event size

       MAX    maximum I/O event size

       AVG    average I/O event size

       KR     total kilobytes read during sample

       KW     total kilobytes written during sample

       DEVICE device name

       MOUNT  mount point

       FILE   filename (basename) for I/O operation

       TIME   timestamp, string

IDEA

       Ryan Matteson

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

       iopattern will run forever until Ctrl-C is hit, or the specified count is reached.

AUTHOR

       Brendan Gregg [Sydney, Australia]

SEE ALSO

       iosnoop(1M), iotop(1M), dtrace(1M)

version 0.70							   Jul 25, 2005 						     iopattern(1m)

Check Out this Related Man Page

execsnoop(1m)							   USER COMMANDS						     execsnoop(1m)

NAME

       execsnoop - snoop new process execution. Uses DTrace.

SYNOPSIS

       execsnoop [-a|-A|-ejhsvZ] [-c command]

DESCRIPTION

       execsnoop prints details of new processes as they are executed.	Details such as UID, PID and argument listing are printed out.

       This  program  is  very	useful	to examine short lived processes that would not normally appear in a prstat or "ps -ef" listing. Sometimes
       applications will run hundreds of short lived processes in their normal startup cycle, a behaviour that is easily monitored with execsnoop.

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

OPTIONS

       -a     print all data

       -A     dump all data, space delimited

       -e     safe output, parseable. This prevents the ARGS field containing "
"s, to assist postprocessing.

       -j     print project ID

       -s     print start time, us

       -v     print start time, string

       -Z     print zonename

       -c command
	      command name to snoop

EXAMPLES

       Default output, print processes as they are executed,
	      # execsnoop

       Print human readable timestamps,
	      # execsnoop -v

       Print zonename,
	      # execsnoop -Z

       Snoop this command only,
	      # execsnoop -c ls

FIELDS

       UID    User ID

       PID    Process ID

       PPID   Parent Process ID

       COMM   command name for the process

       ARGS   argument listing for the process

       ZONE   zonename

       PROJ   project ID

       TIME   timestamp for the exec event, us

       STRTIME
	      timestamp for the exec event, string

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

       execsnoop will run forever until Ctrl-C is hit.

AUTHOR

       Brendan Gregg [Sydney, Australia]

SEE ALSO

       dtrace(1M), truss(1)

version 1.20							   Jul 02, 2005 						     execsnoop(1m)
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