rwsnoop(1m)

NAME
rwsnoop - snoop read/write events. Uses DTrace.

SYNOPSIS
rwsnoop [-jPtvZ] [-n name] [-p PID]

DESCRIPTION
This is measuring reads and writes at the application level. This matches the syscalls read, write, pread and pwrite. Since this uses DTrace, only users with root privileges can run this command.

OPTIONS

-j  print project ID

-P  print parent process ID

-t  print timestamp, us

-v  print time, string

-Z  print zone ID

-n name
    process name to track

-p PID
    PID to track

EXAMPLES

Default output,
    # rwsnoop

Print zone ID,
    # rwsnoop -

Monitor processes named "bash",
    # rwsnoop -n bash

FIELDS

TIME
    timestamp, us

TIMESTR
    time, string

ZONE
    zone ID

PROJ
    project ID

UID user ID

PID process ID

PPID
    parent process ID

CMD command name for the process

D   direction, Read or Write

BYTES
    total bytes during sample

FILE
    filename, if file based. Reads and writes that are not file based, for example with sockets, will print "<unknown>" as the filename.

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

EXIT
rwsnoop will run forever until Ctrl-C is hit.

AUTHOR
Brendan Gregg [Sydney, Australia]

SEE ALSO
rwtop(1M), dtrace(1M)