A parallel version of the ARPACK library is also available. The message passing layers currently supported are BLACS and MPI. Parallel ARPACK (P_ARPACK) is provided as an extension to the current ARPACK library. P_ARPACK has been installed on CRAY-T3D, Intel Delta and Paragon, Intel Paragon IBM-SP2, an SGI cluster and a network of Sun workstations. The package runs efficiently in each of these environments. More detailed information about Parallel ARPACK is available in the report  by Maschhoff and Sorensen.