trace – show (real–time) process behavior

trace [ –d file ] [ –v ] [ –w ] [ pid ... ]

Trace displays the behavior of processes running on the machine. In its window it shows a time line for each traced process. Running processes appear as colored blocks, with arrows marking important events in real–time processes (see proc(3)). Black up arrows mark process releases, black down arrows mark process deadlines, green down arrows mark times when a process yielded the processor before its deadline, red down arrows mark times when the process overran its allotted time.

Trace reads /proc/trace to retrieve trace events from the kernel scheduler. Trace events are binary data structures generated by the kernel scheduler. It is assumed that the reader of /proc/trace and the kernel providing it have the same byte order.

The options are:
d    specify an alternate trace event file
v    print events as they are read from the trace event file
w    run in a new window rather than using the current one

Trace recognizes these keystroke commands while it is running:
+     zoom in by a factor of two
–     zoom out by a factor of two
p     pause or resume
q     quit


/proc/trace           trace event file
/sys/include/trace.h   trace event data structures