On Mon, 7 Apr 2008, amjad ali wrote: > *Hello all, > > I installed PETSc with intel compilers. Please comment on that what is the > difference between the PETSc installed with gnu compilers and the PETSC > installed with intel compilers. Any difference in efficiency? or what so > ever? > > What you say if we intall PETSc with PGI compilers and also we use > MPI-profiler/debugger (available in PGI Cluster Toolkit) for PETSc > applications? Is it possible? and beneficial?
We expect Intel compilers to be able to optimize code better than GNU compilers. Perhaps PGI might do the same. Its best to run your code [with PETSc compiled with the desired compilers - and optimization options] and run with -log_summary to compare performance differences. And we have no experience with PGI Cluster Toolkit or its usefulness. Note: The choice of compilers [and their cost/benifit] varies depending on the usage. - For code development - debuggability matters. gnu compilers work reasonably well for this usage [with gdb, valgrind, etc..] - For production runs, a 10% performance difference might not matter for code that runs for less than an hour. But it might be significant for long-running jobs. etc.. Satish
