Overwriting PILAENV

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Unfortunately, Intel for some reason decided to set the return value of PILAENV (the recommended block size) for their ScaLAPACK implementation to 512. This value gives less than ideal performance (on Intel's own CPUs!) and I am confused why they did it. Is there a way to overwrite this value, e.g. by an environment variable?

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pilaenv returns the positive integer value of the logical blocking size. This value is machine and precision specific. This version provides a logical blocking size which should give good though not optimal performance on many of the currently available distributed-memory concurrent computers. You are encouraged to modify this subroutine to set this tuning parameter for your particular machine. You are encouraged to modify this subroutine to set the tuning parameters for your particular machine using the option and problem size information in the arguments.