7 ms·
Can anyone hazard a guess as to how Linus was able to measure the cost of a page fault and an iret so precisely? What tools and techniques might he have used?
by michaelf 12y ago
Can anyone hazard a guess as to how Linus was able to measure the cost of a page fault and an iret so precisely? What tools and techniques might he have used?
- zerohp 12y agoI don't know what he used, but its probably based on the model specific registers for performance counters. See Chapter 18 of the Intel 64 and IA-32 Architectures Software Developer's Manual.
- apw 12y agoIt'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