Guide to setting environment variables in DataStage
This section gives some guide as to which environment variables should be set in what circumstances.
Environment variable settings for all DataStage jobs
The following environment variables are recommended for all jobs.
Optional environment variable settings in DataStage
The following environment variables are recommended on a per-job basis.
These variables can be used to turn the performance of a particular job flow, to assist in debugging, and to change the default behavior of specific parallel job stages.
Performance tuning environment variables in DataStage
The following environment variables are recommended for performance tuning of a job flow.
- APT_BUFFER_MAXIMUM_MEMORY environment variable in DataStage
- APT_BUFFER_FREE_RUN environment variable in DataStage
- TMPDIR. This defaults to /tmp. It is used for miscellaneous internal temporary data, including FIFO queues and Transformer temporary storage. As a minor optimization, it can be better to ensure that it is set to a file system separate to the DataStage install directory.
DataStage job flow debugging
The following environment variables are recommended to assist in debugging.
Job flow design environment variables in DataStage
The following environment variables are recommended to assist in job flow design.