Description of problem: DTrace / SystemTAP provide a flexible framework for efficient tracing of live applications. For userspace applications this requires that markers be inserted in the code in the interesting trace locations. SystemTAP uses the DTrace marker format, so it is only neccessary to have one impl of these markers for both Linux and Solaris. At the very least libvirt should provide - Tracepoints at all public API entry points - Tracepoints in interesting places in libvirtd (client connect, disconnect, RPC message dispatch queues, and authentication points) - Tracepoints in key parts of the internal hypervisor drivers - Tracepoints in key parts of the storage drivers As an example of how "simple" it is to get a minimal probe set working, this GNOME GLib patch is a great reference point to follow http://bugzilla-attachments.gnome.org/attachment.cgi?id=150787 https://bugzilla.gnome.org/show_bug.cgi?id=606044 http://blogs.gnome.org/alexl/2010/01/04/tracing-glib/ Version-Release number of selected component (if applicable): 0.7.5 How reproducible: Steps to Reproduce: 1. 2. 3. Actual results: Expected results: Additional info:
A basic proof of concept inserting 8 probes into libvirtd is available for review: https://www.redhat.com/archives/libvir-list/2010-September/msg00238.html
Stan has offered to review the "for some reason, we need to restart libfirt" funny business.
This was merged a long time ago.