On Thu, Oct 20, 2011 at 12:53 PM, Andi Kleen <a...@firstfloor.org> wrote: >> This warnings/notes are caused >> by inconsistent profile due to data race (which is currently common in >> multi-thread programs), > > I never quite understood why the gcov counters are not simply marked > __thread. This would make the profiled programs faster too because > they wouldn't bounce cache lines that much. Especially on larger > systems (>2S) frequent cache line bouncing can lead to extreme slow downs, > and even on smaller systems it's very expensive. > This would also eliminate data races, except for signals and somesuch.
It uses stack space and for programs with hundreds and thousands of threads, it can be a big problem. David > > -Andi > >
