C++ Compilers : Comparative Performance Testsuite

["Alex Vinokur" <alexvn at connect dot to>]

An algorithm which computes very long Fibonacci numbers
  http://groups.google.com/groups?selm=bnni5p%2412i47o%241%40ID-79865.news.uni-berlin.de
  was used as a performance testsuite
  to compare speed of the code produced by various compilers.


===========================================================
Windows 2000 Professional Ver 5.0 Build 2195 Service Pack 2
Intel(R) Celeron(R) CPU 1.70 GHz
GNU time 1.7 (Cygwin; to get the real time used)
===========================================================


A. Real and processor time used to compute
   * Fibonacci[10000],
   * Fibonacci[25000],
   * Fibonacci[50000]
   has been measured.

   Here are summary results.

|========================================================================|
|                      | Opt |  Fib-10000  |  Fib-25000  |   Fib-50000   |
|       Compiler       | Lev |-------------|-------------|---------------|
|                      |     | Real : CPU  | Real : CPU  | Real  :  CPU  |
|========================================================================|
|                            GNU gcc compiler                            |
|------------------------------------------------------------------------|
| g++ 3.3.1 (Cygwin)   | No  | 0.45 : 0.41 | 1.86 : 1.81 |  6.63 :  6.58 |
|                      | O1  | 0.28 : 0.24 | 1.03 : 0.99 |  3.87 :  3.60 |
|                      | O2  | 0.27 : 0.23 | 1.02 : 0.98 |  3.79 :  3.73 |
|                      | O3  | 0.27 : 0.24 | 1.02 : 0.98 |  3.81 :  3.74 |
|                      |     |      :      |      :      |       :       |
| g++ 3.3.1 (Cygwin)   | No  | 0.33 : 0.30 | 1.59 : 1.56 |  5.71 :  5.66 |
| Mingw32 interface    | O1  | 0.20 : 0.16 | 0.87 : 0.84 |  3.02 :  2.97 |
|                      | O2  | 0.19 : 0.16 | 0.85 : 0.82 |  2.97 :  2.91 |
|                      | O3  | 0.19 : 0.16 | 0.85 : 0.82 |  2.98 :  2.93 |
|                      |     |      :      |      :      |       :       |
| gpp 3.2.1 (DJGPP)    | No  | 0.37 : 0.24 | 1.99 : 1.92 | 10.53 : 10.42 |
|                      | O1  | 0.20 : 0.11 | 1.15 : 1.05 |  7.48 :  7.37 |
|                      | O2  | 0.19 : 0.11 | 1.08 : 0.99 |  7.23 :  7.12 |
|                      | O3  | 0.19 : 0.11 | 1.08 : 0.99 |  7.25 :  7.12 |
|                      |     |      :      |      :      |       :       |
|------------------------------------------------------------------------|
|               Digital Mars C/C++ Compiler, STLport 4.5.3               |
|------------------------------------------------------------------------|
| Version 8.35n        | -   | 0.20 : 0.16 | 0.84 : 0.80 |  3.82 :  3.74 |
|========================================================================|



B. The names of DLL files on which the programs depend :

   * g++ 3.3.1 (Cygwin)
     ------------------
     C:\cygwin\bin\cygwin1.dll
       C:\WINNT\System32\KERNEL32.dll
         C:\WINNT\System32\NTDLL.DLL


   * g++ 3.3.1 (Cygwin, Mingw32 interface)
     -------------------------------------
      C:\WINNT\System32\msvcrt.dll
        C:\WINNT\System32\KERNEL32.dll
          C:\WINNT\System32\NTDLL.DLL


   * gpp 3.2.1 (DJGPP)
     -----------------
     DJGPP doesn't support dynamic linking.


   * Digital Mars C/C++ 8.35n
     ------------------------
     C:\WINNT\System32\KERNEL32.DLL
       C:\WINNT\System32\NTDLL.DLL
     C:\WINNT\System32\USER32.DLL
       C:\WINNT\System32\GDI32.DLL



C. Notes.
     -----------------------------
     Note-1. The main() program in
             http://groups.google.com/groups?selm=bnni5p%2412i47o%241%40ID-79865.news.uni-berlin.de
             was slightly changed to get the processor time used.

     // ------ Updated main() : BEGIN ------
     #include <time.h>   // Added
     int main (int argc, char **argv)
     {
     const string option (check (argc, argv));
       if (option.empty())
       {
         usage (argv);
         return 1;
       }

     const uint N = atoi (argv[2]);

     const clock_t clock_start = clock();       // Added
       assert (clock_start != clock_t (-1));    // Added

       if (option == ALL_FIBS)
       {
         Fibonacci fib(N);
         fib.show_all_numbers();
       }

       if (option == TH_FIB)
       {
         Fibonacci fib(N);
         fib.show_last_number();
       }

       if (option == SOME_FIBS)
       {
         Fibonacci fib;
         for (int i = 2; i < argc; i++) fib.show_number (atoi(argv[i]));
       }

       if (option == RAND_FIBS)
       {
         const int max_rand_fib = (argc == 3) ? MAX_RAND_FIB : atoi (argv[3]);
         Fibonacci fib;
         for (uint i = 0; i < N; i++) fib.show_number (rand()%max_rand_fib);
       }

       // ------ Added : BEGIN ------
     const clock_t clock_end = clock();
       assert (clock_end != clock_t (-1));

       cerr << "CPU  time used : " << (double (clock_end - clock_start)/CLOCKS_PER_SEC) << " sec" << endl;
       // ------ Added : END --------

       return 0;
     }
     // ------ Updated main() : END --------



     -----------------------------
     Note-2. To get the real time used the time() utility was used.



--
 =====================================
   Alex Vinokur
     mailto:alexvn@connect.to
     http://mathforum.org/library/view/10978.html
     news://news.gmane.org/gmane.comp.lang.c++.perfometer
   =====================================






--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/