On Friday 03 June 2011, Frank Chang wrote: > At the beginning of a program period you want to profile, set the counters > to zero (add "CALLGRIND_ZERO_STATS;" > into your source), and at the end, dump the profile to a file (add > "CALLGRIND_DUMP_STATS;" into your source code). > > > However, we found found that that callgrind 3.6.1 on Centos Linux > Version 5.5 x86_32 takes 10 times longer to run even in those parts of > the program that are not be selectively profiled
These macros do not influence whether simulation is done or not. So, of course, the simulation is running all the time. Switching off/on simulation can be done via the macros CALLGRIND_STOP_INSTRUMENTATION and CALLGRIND_START_INSTRUMENTATION There is an issue here: Switching instrumentation on will clean the cache state, so there will be a lot of misses directly after it, which would not happen in reality. So in principle, you should switch on instrumentation some time before zeroing counters for start of measurement. However, the error usually is small even if you directly start measurement when starting full instrumentation. Josef ------------------------------------------------------------------------------ Simplify data backup and recovery for your virtual environment with vRanger. Installation's a snap, and flexible recovery options mean your data is safe, secure and there when you need it. Discover what all the cheering's about. Get your free trial download today. http://p.sf.net/sfu/quest-dev2dev2 _______________________________________________ Valgrind-users mailing list Valgrind-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/valgrind-users
