henley@athena.ee.msstate.edu (Greg Henley) (12/04/89)
I recently obtained a 2000-3000 line CFD (Computational Fluid Dynamics) program which was written in Fortran and which requires a considerable amount of storage space and cpu time (approx. 65 meg and 2 hours to run one cycle on a Sun 4/280). From previous experience on other C and Fortran programs, full optimization could give a 2 to 3 times speedup. However, when I try optimization level -O2 or -O3, the program crashes with a huge core dump. Level -O1 works but doesn't give any noticeable improvement in execution time. We are running SunOS 4.0.3 and have Fortran version 1.2. Has anyone else experienced this? If so, is there a bug fix? I was able to compile it on another Sun which was running SunOS 4.0 and Fortran version 1.1. Level -O3 worked with no apparent problems and gave about a 2 times speedup. Any help appreciated. Greg Henley, Research Engineer Mississippi State University Dept. of Electrical Engineering INET: henley@ee.msstate.edu