Re: PThread profiling

[Josh Stone <jistone at redhat dot com>]

Daniel Tralamazza wrote:
> I even did a tapset for most pthread functions inside NPTL
> ('probe pthread.create').

I think such a tapset would have general interest, even with the slower 
uprobe version.  You could define the tapset to work with both the base 
glibc and your patched version:

probe pthread.create = process(...).mark(...)!,
                       process(...).function(...)
{ ... }

> It worked fine, but the overhead was causing measurements errors
> (too slow == higher contention probability). It was clear that I
> had to use static markers, all I had to do was patch glibc/nptl
> and voila.

Can you share performance numbers on this?  I'd like to see the 
comparison of unprobed, function uprobes, and static markers...

Josh