On Saturday 24 January 2009, Thomas Thrainer wrote: > Hello, > > I'm trying to profile an application on the N810 with gprof. I compiled it > with -pg, -O3 and -g and linked all the libraries I'm interested in > statically (and compiled them also with -pg -O3 -g). > > The first couple of problems were that I got a floating point exception in > scratchbox when starting the program, and a crash on the tablet. Using > -fno- unit-at-a-time and -fno-omit-frame-pointer solves the problem on the > tablet, it still doesn't run in scratchbox tough. By the way, this is > related to -O3, non-optimized build run fine in both scratchbox and on the > tablet. > > My problem is however, that profiling doesn't give any usable results. In > the profile written to gmon.out there are all times 0.0. But the call graph > and calling count for functions is correct. > > I tried to strace the application, and profiling seems to work normally. > The profiling code sets up the profiling timer, and the SIGPROF signal is > received regularly throughout the program run. > So I suspect the profiling code, or more precisely the SIGPROF-handler, to > not being able to get the currently executing function based on the stack. > My program is not spending a lot of time in some library functions or such, > most of the time it's usually in some user-functions (I know that based on > profiling on my PC). > > Can anybody shed some light on this issue? To I have to link against some > special version of glibc? Or is profiling with gprof broken on ARM's?
IIRC, there might be something wrong with the toolchain in the respect of support for -pg option. On the other hand, do you really need to use gprof? Profiling on N810 can be done with oprofile, which covers all the gprof functionality and provides a lot more features. Please check the following page: http://maemo.org/development/tools/doc/diablo/oprofile/ If you think that for your specific case gprof is better and doubt that oprofile can handle it well, please describe what exactly you want to do. I'll try to advice something. -- Best regards, Siarhei Siamashka _______________________________________________ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers
