Common Set of Environment Variables

BC Project: FY05-04
Date of Policy: 14 Jul 2005
Last Updated: 16 Mar 2012 (see Revision Log)

This policy was written to define a core set of environment variables that represent the same thing at each of the HPCMO allocated centers participating in the Baseline Configuration (BC) Initiative. These variables shall be pre-defined in all login scripts, making them automatically available to users at each center.

The current list of variables is as follows:

ARCHIVE_HOME

This is an individual user's directory on the archival file system that serves a given compute platform. ARCHIVE_HOME is intended to be used as a long-term file storage area by a user. It is not intended to be used by executing programs as this can significantly slow the I/O portion of a program.

Note this environment variable becomes unnecessary and should be undefined once Storage Lifecycle Management (SLM) goes into production at a center.

ARCHIVE_HOST

This is the hostname of the archival system serving a particular compute platform. In cases where the archival system is not network mounted to the compute platform, the combination of ARCHIVE_HOST and ARCHIVE_HOME will give the exact location of a user’s long-term archival storage.

Note this environment variable becomes unnecessary and should be undefined once Storage Lifecycle Management (SLM) goes into production at a center.

BC_CORES_PER_NODE

This variable contains the number of cores per node for the compute node type to which a job is being submitted.

BC_HOST

This variable should be defined as the generic (not node specific) name of the system. Examples include Raptor, Diamond, Einstein, etc.

BC_MEM_PER_NODE

This variable contains the approximate maximum memory per node available to an end user program (in integer MBytes) for the compute node type to which a job is being submitted.

BC_MPI_TASKS_ALLOC

This variable, intended to be referenced from inside a job script, shall contain the number of MPI tasks that are allocated for a particular job.

BC_NODE_ALLOC

This variable, intended to be referenced from inside a job script, shall contain the number of nodes allocated for a particular job.

CC

This variable should be set by any system supporting a C compiler. If a default compiler is provided, this variable should be set to the default C compiler. Any subsequent change to the C compiling environment should reset this variable to the C compiler for that environment. The variable refers to the compiler required for program execution on the compute nodes.

CENTER

This variable contains the path for a user’s directory on the Center Wide File System (CWFS).

CSI_HOME

This variable contains the path to the base directory for the application codes installed on a system under the Consolidated Software Initiative (CSI).

CXX

This variable should be set by any system supporting a C++ compiler. If a default compiler is provided, this variable should be set to the default C++ compiler. Any subsequent change to the C++ compiling environment should reset this variable to the C++ compiler for that environment. The variable refers to the compiler required for program execution on the compute nodes.

DAAC_HOME

This variable contains the path to the base installation directory of the ezViz visualization software package. See BC Policy FY08-01 entitled "ezViz Visualization Tool" for more information.

F77

This variable should be set by any system supporting a Fortran 77 compiler. If a default compiler is provided, this variable should be set to the default Fortran 77 compiler. Any subsequent change to the Fortran 77 compiling environment should reset this variable to the Fortran 77 compiler for that environment. The variable refers to the compiler required for program execution on the compute nodes.

F90

This variable should be set by any system supporting a Fortran 90 compiler. If a default compiler is provided, this variable should be set to the default Fortran 90 compiler. Any subsequent change to the Fortran 90 compiling environment should reset this variable to the Fortran 90 compiler for that environment. The variable refers to the compiler required for program execution on the compute nodes.

JAVA_HOME

This variable contains the path to the base directory of the default installation of JAVA on a particular compute platform.

KRB5_HOME

This variable should be set to point to the installation directory of the Kerberos utilities.

PET_HOME

This variable contains the path to the system-wide accessible directory containing the tools installed by the PETTT ACE staff.

PROJECTS_HOME

This variable contains the path to the base directory that will contain directories for user-supported applications and codes under BC Policy FY10-07 entitled "Common Location to Maintain Codes"

SAMPLES_HOME

This variable contains the path to the base directory for the sample codes and scripts installed by a center's staff under BC Policy FY06-15 entitled "Sample Code Repository."

WORKDIR

This is an individual user's directory on the local temporary file system (i.e., local high speed disk) that is available on all HPCMP high performance computing (HPC) systems. WORKDIR is intended to be used by executing programs to perform file I/O that is local to that system in order to avoid slower file I/O across a network mounted file system, such as a user's home or archive directories. It is not intended to be used as a permanent file storage area by users. Accordingly, this file system is NOT backed up or exported to any other system. In the event of file or directory structure deletion or a catastrophic disk failure, such files and directory structures are lost.

Thus, it is the user's responsibility to transfer files that need to be saved to a location that allows for permanent file storage, such as the user's archival or home directory locations.

This list of environment variables is subject to change, and should be reviewed on a periodic basis for potential additions or deletions.