| commit | a0ae83d0fdee0690b8b1b660a6a656bda5891a37 | |
| author | Keith Adams <kma@fb.com> | |
| Thu, 27 Jun 2013 21:35:22 +0000 (27 14:35 -0700) | ||
| committer | Sara Golemon <sgolemon@fb.com> | |
| Mon, 1 Jul 2013 20:40:55 +0000 (1 13:40 -0700) | ||
| tree | 3b70b7d1f5ab5cc7a03c1bf7f47cbbab2f4e316f | treesnapshot (tar.gz zip) |
| parent | 652f0e7b2a6db3e11f78b720f08dcb66751ec66a | commitdiff |
Introduce rdtsc, cycle delay primitives.
I keep reintroducing these by hand. My workflow is usually:
1. Have an idea to optimize X.
2. Realize I don't even know if X is important or not.
3. Instrument X to slow it down, to see if it makes a difference in
perflab.
After this diff, 3 is a simple matter of inserting a call to
cycleDelay(1000) (or what have you) in the path of interest.
I keep reintroducing these by hand. My workflow is usually:
1. Have an idea to optimize X.
2. Realize I don't even know if X is important or not.
3. Instrument X to slow it down, to see if it makes a difference in
perflab.
After this diff, 3 is a simple matter of inserting a call to
cycleDelay(1000) (or what have you) in the path of interest.
| hphp/runtime/ext/ext_hotprofiler.cpp | diffblobblamehistory | |
| hphp/runtime/vm/jit/translator-x64.cpp | diffblobblamehistory | |
| hphp/util/cycles.h | [new file with mode: 0644] | blob |