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Linux versus Windows....

Posted: Fri Oct 10, 2008 8:58 pm
by Michel
Hi,

I wrote a little generic bench marking utility for UCI engines. See

http://alpha.uhasselt.be/Research/Algeb ... nch/devel/

The idea was to be able to quickly and routinely compare different OS'es, CPU's, compilers etc (for the same engine). This came out of some discussions at the Toga development forum.

I ran some tests in Linux and Windows. You can find the results on the above URL. The tests were run on a laptop with a Pentium M@1.6GHz.

Two noteworthy conclusions.

(1) A Windows engine generally runs at the same speed under wine as on native Windows.

(2) I made a Linux binary of Toga II 1.4b5c with the Intel compiler. Strangely enough it seems to run slower than the corresponding Windows binary which is made with the same compiler. I suspect this is an issue of compiler options. I still have to investigate this (although any pointers to "magic" compiler options would be welcome).

I am kind of curious what the situation on OSX is.

Regards,
Michel

Re: Linux versus Windows....

Posted: Fri Oct 10, 2008 11:51 pm
by Michael Sherwin
How a program lines up in memory from one compile to the next makes a difference. If a single line of code in a non time critical section is added the program may run slower. Add a line of code that is not cheap to a time critical section and the program might run faster!

Re: Linux versus Windows....

Posted: Sat Oct 11, 2008 4:33 pm
by Michel
(2) I made a Linux binary of Toga II 1.4b5c with the Intel compiler. Strangely enough it seems to run slower than the corresponding Windows binary which is made with the same compiler. I suspect this is an issue of compiler options. I still have to investigate this (although any pointers to "magic" compiler options would be welcome).


It appears that the secret is profiling. Using the profiling facilities of the Intel compiler I could make a Linux binary of Toga II 1.4b5c which seems to run faster on my system (a Pentium M@1.6GHz) than the standard Windows binary (as measured by my utility). See

http://alpha.uhasselt.be/Research/Algeb ... _versions/

The numbers are

Code: Select all

Toga II       1.4b5c      windows               584k
Toga II       1.4b5c       wine                 580k
Toga II       1.4b5c    linux/intel             599k
Toga II       1.4b5c    linux/gcc 4.2           484k
Regards,
Michel