| .TH reset-trace 8 "2016-10-18" "USER COMMANDS" |
| .SH NAME |
| reset-trace \- reset the state of tracing. |
| .SH SYNOPSIS |
| .B reset-trace [\-F] [\-h] [\-q] [\-v] |
| .SH DESCRIPTION |
| You will probably never need this tool. If you kill \-9 a bcc tool (plus other |
| signals, like SIGTERM), or if a bcc tool crashes, then kernel tracing can be |
| left in a semi-enabled state. It's not as bad as it sounds: there may just be |
| overhead for writing to ring buffers that are never read. This tool can be |
| used to clean up the tracing state, and reset and disable active tracing. |
| |
| Make sure no other tracing sessions are active. This tool might stop them from |
| functioning (perhaps ungracefully). |
| |
| This specifically clears the state in at least the following files in |
| /sys/kernel/debug/tracing: kprobe_events, uprobe_events, trace_pipe. |
| Other tracing facilities (ftrace) are checked, and if not in an expected state, |
| a note is printed. All tracing files can be reset with \-F for force, but this |
| will interfere with any other running tracing sessions (eg, ftrace). |
| .SH REQUIREMENTS |
| /sys/kernel/debug mounted as debugfs |
| .SH OPTIONS |
| .TP |
| \-F |
| Force. Will reset all tracing facilities, including those not used by bcc |
| (ftrace). You shouldn't need to use this. |
| .TP |
| \-h |
| USAGE message. |
| .TP |
| \-q |
| Quiet. No output while working. |
| .TP |
| \-v |
| Verbose: print what it is doing. |
| .SH EXAMPLES |
| .TP |
| Reset the state of tracing: |
| # |
| .B reset-trace |
| .TP |
| Verbose: |
| # |
| .B reset-trace \-v |
| .TP |
| .SH SOURCE |
| This is from bcc. |
| .IP |
| https://github.com/iovisor/bcc |
| .PP |
| Also look in the bcc distribution for a companion _examples.txt file containing |
| example usage, output, and commentary for this tool. |
| .SH OS |
| Linux |
| .SH STABILITY |
| Unstable - in development. |
| .SH AUTHOR |
| Brendan Gregg |