A..3.5 Adjusting the default environment for MOLPRO

The default running options for MOLPRO are stored in the file bin/molpro.rc. After program installation, either using RPMs or from source files, this file should be reviewed and adjusted, if necessary. Particular attention should be payed to some or all of the following (see User's manual for full discussion of options).

-d dir1:dir2:$\dots$

where dir1:dir2:$\dots$ is a list of directories which may be used for creating scratch files. Each of the directories should be writable by those who will use the program, and the directory specification may contain embedded environment variables in shell form, for example $TMPDIR or /tmp/$USER; these will be expanded at run time. If multiple scratch file systems are available, it is advantageous to present a list of directories of which there is one in each file system. Some parts of MOLPRO present extreme I/O demands, and it is therefore important to be careful in optimizing the provision and specification of scratch directories.

Note that in the building of bin/molpro.rc, the environment variables $TMPDIR, $TMPDIR2, $TMPDIR3,$\dots$ are used to construct the list of scratch directories for the -d option. Thus, these environment variables should at make time be filled with the names of directories on each available scratch file system (cf. section A.3.3).

-I directory

This determines the destination of permanent integral files. At run time this file is located in the first directory specified after -d, (i.e., dir1, see above), but after completion of the job the file will be copied to the directory given after -I. Since the integral file can be very large, it is normally recommended that directory is identical to dir1 (this is the default). Then no copying will take place. On some main frames, the scratch directory is erased automatically after a job has terminated, and in such cases a different -I directory, e.g., $HOME/int, can be specified (environment variables will be expanded at run time). In view of the large integral file sizes, this should be used with care, however. Note that in parallel runs with more than 1 processor the integral file will never be copied, and cannot be restarted.

-W directory

This determines the destination of permanent wavefunction (dump) files used for storing information like orbitals or CI-vectors etc. These files are essential for restarting a job. As explained for the integral files above, permanent wavefunction files will be copied to directory after completion of the job. The default for directory is $HOME/wfu.

-k key

where key is the licence key, obtainable as described in section A.1.

-m, -G

The default local memory and GA memory should be checked to be appropriate for the hardware environment.

-n, -N

The number of processors or their identity can be specified explicitly in the configuration file, but very often it is neither desirable nor necessary to do so. Where possible, the molpro program extracts a reasonable default for the node specification from the controlling batch system (e.g. LoadLeveler, PBS). Usually the user will want to either specify -n explicitly on the command line, or rely on molpro's attempts to get it from the batch system.