ETL Processes are always complex, resource and time consuming. All is based on complexity of Business Logic, amount of Data Processed and various data sets and data sources which are growing regularly. Even then SLA is same as it was decided initially without considering current rate of Data Growth. As all about Data and information need to be provided on time, Performance is key element in the success of any BI and DW Project. To meet the agreed SLA and provide timely information performance tuning and configuration of various Parameters is the Key. It requires to be given appropriate attention during the DW and ETL development process. Now when we talk about InfoSphere DataStage, it is not an easy task. No tuning is Straightforward.
Below link discusses various aspects need to be considered during Performance Tuning.
IBM InfoSphere DataStage Performance Tuning: Overview of Best Practices
-Ritesh
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