Vladimir N. Makarov wrote: > Eric Botcazou wrote: >>> Please, just look at those charts >>> >>> https://vmakarov.108.redhat.com/nonav/spec/comparison.html >>> >>> The compilation speed decrease without a performance improving (at least >>> for the default case) is really scary. >>> >> >> Right, I also found those charts a bit depressing, given the time and >> energy that have been put in the compiler since GCC 3.2.3.
To cheer you up, you can look at the number for gfortran with the Polyhedron benchmark: http://physik.fu-berlin.de/~tburnus/gcc-trunk/benchmark/#rt gfortran 4.1.3 is up to 119% slower than gfortran 4.3, whereas the speed regressions are maximally 12%. For the geometric mean, gfortran 4.2 needs 12% longer than 4.3 (All values for AMD64.) Looking at the geometric mean of the 16 tests, 4.3. is only 5% slower than Intel's ifort 9.1, 6% than ifort 10.0 and sunf95, and 16% slower than Pathscale.* I think this is not bad at all! Tobias PS: The df merge has caused speed regression (geometric mean) of around 1%. *One can probably better tune the parameter of all the compilers.
