Debugging/Tool support in NPTL

Hi Ulrich,

Do you have a row idea about how much work (in people.month)
it would need for building each part of a Debugging/Tracing
tool for NPTL ?
 - NPTL part: tracing support inside NPTL.
 - Tool part: simple tool displaying the trace of NPTL, after a run.

Do you know about some Linux Tracing tool that could/should
be extended with this NPTL trace tool ?

I think adding some OpenSource light tool that shows the main
events of a multi-threaded application without modifying its
behaviour will help end-users.
For me, a "light tool" means some tool that provides main trace
features, easy to use and to understand, with few configuration
features. (It should not be TOO light ...).
What's your opinion ?

I'm new within Linux kernel. Is there some "kernel trace"
mechanism that should be reused ?

Amicalement/Regards,

Tony Reix

                            Carpe Diem