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]