LTTng simple trace
Requesting a new command in lttng-tools
the name should be something like trace and the functionality should be similar to strace.
the syntax could be something like
lttng trace program_name program_args
let's say you instrumented ls, then lttng trace ls -l /dev would trace ls going through the directory.
The traces taken should be both kernel and UST unless otherwise specified.
The timestamps for user space and kernel space should be on the same base. (Offsets will make this unusable by most)
the command sequence internally could be as simple as
lttng create default_name; lttng enable-event -a -k ; lttng enable-event -a -u; lttng start; %program_name; lttng stop; lttng destroy;
If the person is not in the tracing group or root, the kernel trace should be unavailable with a warning. if the application is not instrumented, it should warn too. if the kernel and userspace tracer is not available, it should warn that too but still run.
These ideas are very open for discussion
Updated by Matthew Khouzam about 8 years ago
After discussing the feature may be poorly described, what I want is this.
Bob is a user
his ID is in the tracing group,
he wants to trace his hello world app
he types "lttng simpleTrace helloWorld"
the program is launched and executes
when it is finished executing, a trace of UST and the kernel are available to read.
Bob traced the program without knowledge of sessions or domains or even tracepoints.
Optional: Bob is so happy he tells his friends. He is awarded a small island in the azores as a reward for his awesomeness.