Here is a comparison of run-times of a C-code that intergrate the complex Ginzburg-Landau equation (CGLe) using 256 points in space, and 50000*50 steps in time. the time-interval $dt$ is 0.01, and CGLe parameters are $\alpha=1.5$, $\beta=-1.2$, is created that contains 50000*256*2 floats, i.e., the file size is 50000*256*2*4=102.400.000 bytes.

The source code is always the same, but I varied the compiler and/or the compiler options, as well as the machine and the OS used.

Here are the results:

processor OS / platform compiler options time (s)
Celeron 800 (wild) Linux RH 7.2 GCC 2.96 (2000/07/31) -O2 333(n)
PIII 800 (light) Linux RH 7.2 GCC 2.96 (2000/07/31) -O2 274(l)
bi-PIII (zero) Linux RH 7.2 GCC 2.96 (2000/07/31) -O2 263(l)
bi-alpha (hard) Compaq Tru64 Unix V Compaq C V6.3-026 -O2 252(n)
PIII 450 coppermine Win2k + DJGPP 2.03 GCC 3.1 -O2  
PIII 450 coppermine Win2k + Cygwin GCC 3.1 -O2 478(l)
PIII 450 coppermine Win2k + mingw GCC 3.1 -O2  


Nicolas Garnier 2002-08-19