[petsc-users] Problems with the intel compilers

Dominik Szczerba dominik at itis.ethz.ch
Tue Oct 27 17:54:55 CDT 2009

Thanks Ando, I know of the slight speed advantage in some cases on the 
Intel side, but the question was more why the compilation takes so much 


Andreas Grassl wrote:
> Hi Dominik,
> Dominik Szczerba wrote:
>> I have noticed already a longer while ago: setting up PETSc with the
>> Intel compilers (--with-cc=icc --with-cxx=icpc) takes an order of
>> magnitude longer than with the native GNU. The step taking most of the
>> time is configuring mpich. I have tried to configure mpich separately
>> and indeed, with gnu it is a breeze, with intel 10x slower. In both
>> cases, linux both 32 and 64 bit, Ubuntu 9.04 and debian testing. Intel
>> compilers 10.x and 11.x.
>> I just wanted to ask opinion if anybody has similar observations and/or
>> finds using intel worthwhile at all.
> On itanium machines intel compilers produce much faster code compared to
> gnu-compilers. On other machines I did not notice a big speed difference, but I
> think intel compilers produce slightly faster code as well.
> Cheers,
> ando

More information about the petsc-users mailing list