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)