PGSLIB(Parallel Gather-Scatter Library) was developed by Robert Ferrell of Cambridge Power Computing Associates, Ltd.. It is used for high-level parallel communication in CÆSAR. PGSLib has both a serial version, which runs on a single processor, and a parallel version, which allows inter-processor communication.
The parallel version of PGSLIB requires an MPI package, which can be provided by the computer vendor or by MPICH (included with CÆSAR).
CÆSAR can be compiled without PGSLIB, or with the serial or parallel versions of PGSLIB.