27-May-2013 01:13, Vladimir Panteleev пишет:
On Sunday, 26 May 2013 at 20:49:36 UTC, Dmitry Olshansky wrote:
It's the kind of thing that is tremendously hard to measure accurately
since it depends on the workload, architecture and the time spent is
very small. So don't take it by word I'm almost certain that something
is amiss (compiler switches and whatnot).
For such cases, I found Agner's benchmarking utilities to be very
useful. They print exact CPU statistics, such as numbers of micro-ops,
cache misses, mispredicted branches, etc. I've used them very
successfully when tuning my appender implementation.
Yes, Agner is da man. Just hoped I could postpone this but... welcome to
the micro-optimization world I guess.
To use them with D, I modified his C++ program to load a DLL and call a
function, taking the DLL and function names from the command line.
Original program:
http://www.agner.org/optimize/testp.zip
My patch (to load a DLL):
http://dump.thecybershadow.net/5f55e8be5f8cd38ad60f218957ef24bb/PMCTestB.diff
Usage example (sort of):
https://github.com/CyberShadow/DAppenderResearch/blob/master/go-dll.bat
Hope this helps :)
Thanks, I'll try it out. But jezz I have win8 so I'd start with linux
version :)
--
Dmitry Olshansky
