I have problems with fortran programs (weather forecast models) parallized with openmp. When the programs are run for some period the threads hangs. The threads exists, but are using no cpu time. I am using fortran version 7.0. It is 2cpu 2.4 ghz Xeon on a 7500 chipset with hyperthreading. the problem is both when hyperthreading are enabled or not. the linux kernel is 2.4.18-3smp from the Red Hat Linux 7.3 2.96-110. When I using the portland compiler there no problem (but the programs are slower, up to 33%), or on other platforms as True64unix (alpha) or SGI. The programs does not hang at the same place. Sometimes they can run for long period before they hangs.
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