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For MPI jobs, the system provided openmpi will not bind processes to cores by default, as would be the normal default for openmpi. This is set this way way to avoid inadvertently oversubcribing processes on cores. In addition, the system openmpi settings will map processes by socket. This should give a good process distibution distribution in all cases. However, if you wish to use less than 28 processes per node in an MPI job then you may want to map by node to get the most even distibution distribution of processes across nodes. You can do that with the --map-by node option flag to mpirun.
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If you wish to control mapping and binding in a more fine-grained manner, the mapping and binding parameters can be overridden with parameters to mpirun. Openmpi provides many options for fine grained control of process layout. The options that are set by default should be good in most cases but can be overridden with the openmpi options for
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If your job does not use the system openmpi, or does not use MPI, then any desired core binding will need to be set up with whatever mechanism the software uses. Otherwise, there will be no core binding. Again, that may not be a major issue. If your job does not work well with HT then run on a number of cores equal to half of the number of slots requested and the OS scheduler will minimize contention.
new SGE utilities
While SoGE is very similar to previous versions of SGE there are some new utilities that people may find of interest. There are manual pages for each of these.
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