Engineering and Scientific Subroutine Library (ESSL) and Parallel ESSL

ESSL and Parallel ESSL are collections of state-of-the-art mathematical subroutines specifically designed to improve the performance of engineering and scientific applications on the IBM POWER™ processor-based servers and blades. ESSL and Parallel ESSL are commonly used in the aerospace, automotive, electronics, petroleum, utilities and scientific research industries for applications such as:

ESSL and Parallel ESSL support 32-bit and 64-bit Fortran, C and C++ serial, SMP and SPMD applications running under AIX® and Linux®.




ESSL is a collection of high performance mathematical subroutines providing a wide range of functions for many common scientific and engineering applications. The mathematical subroutines are divided into nine computational areas:

ESSL provides the following run-time libraries:

The ESSL Serial Library and the ESSL SMP Library support the following application environments:

All libraries are designed to provide high levels of performance for numerically intensive computing jobs and both provide mathematically equivalent results. The ESSL subroutines can be called from application programs written in Fortran, C, and C++. ESSL running on the AIX and Linux operating systems.

Parallel ESSL

Parallel ESSL

Parallel ESSL

Parallel ESSL is a scalable mathematical subroutine library for standalone clusters or clusters of servers connected via a switch and running AIX and Linux. Parallel ESSL supports the Single Program Multiple Data (SPMD) programming model using the Message Passing Interface (MPI) library. The Parallel ESSL SMP libraries support parallel processing applications on clusters of Power Systems servers and blades connected via a LAN supporting IP or with an InfiniBand switch.

Parallel ESSL provides subroutines in the following computational areas:

For communication, Parallel ESSL includes the Basic Linear Algebra Communications Subprograms (BLACS), which use MPI. For computations, Parallel ESSL uses the ESSL subroutines (ESSL is a pre-requisite).

The Parallel ESSL subroutines can be called from 32-bit and 64-bit application programs written in Fortran, C, and C++ running the AIX and Linux operating systems.

The Parallel ESSL SMP Libraries are provided for use with the IBM Parallel Environment MPI library. You can run single or multithreaded US or IP applications on all types of nodes. However, you cannot simultaneously call Parallel ESSL from multiple threads.

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