The DIII-D computing environment: characteristics and recent changes

The DIII-D tokamak national fusion research facility along with its predece ssor Doublet III has been operating for over 21 years. The DIII-D computing environment consists of: real-time systems controlling the tokamak, heatin g systems, and diagnostics, and systems acquiring experimental data from in strumentation; major data analysis server nodes performing short term and l ong term data access and data analysis; and systems providing mechanisms fo r remote collaboration and the dissemination of information over the world wide web. Computer systems for the facility have undergone incredible chang es over the course of time as the computer industry has changed dramaticall y. Yet there are certain valuable characteristics of the DIII-D computing e nvironment that have been developed over time and have been maintained to t his day. Some of these characteristics include: continuous computer infrast ructure improvements, distributed data and data access, computing platform integration, and remote collaborations. These characteristics are being car ried forward as well as new characteristics resulting from recent changes w hich have included: a dedicated storage system and a hierarchical storage m anagement system for raw shot data, various further infrastructure improvem ents including deployment of Fast Ethernet, the introduction of MDSplus, Lo ad Sharing Facility (LSF) and common IDL based graphics tools, and improvem ents to remote collaboration capabilities. This paper will describe this co mputing environment, important characteristics that over the years have con tributed to the success of DIII-D computing systems, and recent changes to computer systems. (C) 2000 Elsevier Science S.A. All rights reserved.