TRACE-CMD-SNAPSHOT(1) =================== NAME ---- trace-cmd-snapshot - take, reset, free, or show a Ftrace kernel snapshot SYNOPSIS -------- *trace-cmd snapshot* ['OPTIONS'] DESCRIPTION ----------- The trace-cmd(1) snapshot controls or displays the Ftrace Linux kernel snapshot feature (if the kernel supports it). This is useful to "freeze" an instance of a live trace but without stopping the trace. trace-cmd start -p function trace-cmd snapshot -s trace-cmd snapshot [ dumps the content of buffer at 'trace-cmd snapshot -s' ] trace-cmd snapshot -s trace-cmd snapshot [ dumps the new content of the buffer at the last -s operation ] OPTIONS ------- *-s*:: Take a snapshot of the currently running buffer. *-r*:: Clear out the buffer. *-f*:: Free the snapshot buffer. The buffer takes up memory inside the kernel. It is best to free it when not in use. The first -s operation will allocate it if it is not already allocated. *-c* 'cpu':: Operate on a per cpu snapshot (may not be fully supported by all kernels) *-B* 'buf':: If a buffer instance was created, then the *-B* option will operate on the snapshot within the buffer. SEE ALSO -------- trace-cmd(1), trace-cmd-record(1), trace-cmd-report(1), trace-cmd-start(1), trace-cmd-extract(1), trace-cmd-reset(1), trace-cmd-split(1), trace-cmd-list(1), trace-cmd-listen(1) AUTHOR ------ Written by Steven Rostedt, RESOURCES --------- git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/trace-cmd.git COPYING ------- Copyright \(C) 2010 Red Hat, Inc. Free use of this software is granted under the terms of the GNU Public License (GPL).