A small note, callgrind doesn't necessarily have to be all or nothing. You can use the CALLGRIND_START_INSTRUMENTATION and CALLGRIND_STOP_INSTRUMENTATION to st

A small note, callgrind doesn't necessarily have to be all or nothing. You can use the CALLGRIND_START_INSTRUMENTATION and CALLGRIND_STOP_INSTRUMENTATION to start and stop the stats collecting. Start valgrind with the –instr-atstart=no option to disable collecting on everything outside of those blocks. It's still really, really, slow but much faster than when it collects everything.