There's also LTTng which is more mature and, arguably, more powerful too (and it does userspace tracing as well): http://lttng.org/ http://lttng.org/ Full disc

There's also LTTng which is more mature and, arguably, more powerful too (and it does userspace tracing as well): http://lttng.org/ http://lttng.org/ Full disclaimer: I'm am a contributor to the LTTng project.