It's quite likely that he was using `perf': $ perf stat make ... 116,222 page-faults # 0.046 M/sec ... https://perf.wiki.kern

It's quite likely that he was using `perf': $ perf stat make ... 116,222 page-faults # 0.046 M/sec ... https://perf.wiki.kernel.org/index.php/Tutorial https://perf.wiki.kernel.org/index.php/Tutorial