IBM Parallel Environment for Linux™ on POWER™ is a high-function development and execution environment for parallel applications running on one or more System p5™ servers.

Parallel Environment for Linux on POWER can offer High Performance Computing (HPC) customers whose parallel applications use the industry-standard Message Passing Interface (MPI) a tool for creating and using parallel applications with a familiar look and feel. IBM's MPI implementation exploits an enhanced low-level application programming interface (LAPI) designed to increase parallel application performance on clusters made up of IBM POWER servers running the Linux OS.

Version 4.3 provides support for Red Hat Enterprise Linux (RHEL) 4, SLES 9, and SLES 10. Enhancements include:

• Up to 512 nodes and 4,096 tasks are supported.
• A parallel debugger has been added.
• InfiniBand interconnect on SLES 9 is supported.
• SLES 10 support is added.
• IP support is provided on various interconnects; IP mode uses the standard UDP/IP protocol, which is available on many interconnects.
• Performance improvements have been made to selected MPI collective communication subroutines.
• MPI one-sided communication performance has been substantially improved.
• The Parallel Operating Environment will copy user hard limit and soft limit values for non-LoadLeveler^® interactive jobs.