NAME
kdump
—
display kernel trace data
SYNOPSIS
kdump |
[-dHlnRTXx ] [-f
file] [-m
maxdata] [-p
pid] [-t
trstr] [-u
label] |
DESCRIPTION
kdump
displays the kernel trace files
produced with ktrace(1) in human-readable format. By default, the file
ktrace.out in the current directory is displayed,
unless overridden by the -f
option.
The options are as follows:
-d
- Display all numbers in decimal. By default, values are printed out in hexadecimal.
-f
file- Display the specified file instead of ktrace.out. Specifying ‘-’ will read from standard input.
-H
- Display thread identifiers.
-l
- Loop reading the trace file, once the end-of-file is reached, waiting for more data.
-m
maxdata- Display at most maxdata bytes when decoding I/O.
-n
- Suppress ad hoc translations. Normally
kdump
tries to decode many system calls into a more human-readable format. For example, ioctl(2) values are replaced with the macro name and errno values are replaced with the strerror(3) string. Suppressing this feature yields a more consistent output format and is easily amenable to further processing. -p
pid- Show output only for the pid specified.
-R
- Display relative timestamps (time since previous entry).
-T
- Display absolute timestamps for each entry (seconds since the Epoch).
-TR
- If both options are specified, display timestamps relative to trace start.
-t
trstr- Select which tracepoints to display. The argument can contain one or more
of the following letters. By default all trace points except for
X
are enabled. -u
label- Display utrace(2) tracepoints having utrace(2) label label as strings with vis(3) escaping, without ktrace(2) header information.
-X
- Display I/O data with hexadecimal data and printable ASCII characters side by side.
-x
- Display I/O data in hexadecimal.
The -t
and -u
options are mutually exclusive; the last one specified overrides any
previous ones.
FILES
- ktrace.out
- default ktrace dump file
SEE ALSO
HISTORY
The kdump
command appeared in
4.3BSD-Reno.