Some general tips on optimizing Ab Initio performance:

• Table lookups should be avoided by unloading the table to a lookup file. If the lookup table is very small, “Join with DB” should be used for table lookup.
• “Partition by key and sort” should be used instead of using 2 components – “Partition by key” and the “Sort” component.
• If the number of records to be sorted to huge, “check pointed sort” can be used.
• Source files that are repeatedly used should be converted and stored as multifiles.
• Serial files need to be partitioned before applying any of the cleansing / business rules.
• Graphs should be run as parallel as possible to improve performance.
• Unwanted data should be filtered out early in the graph.
• Big Lookup files should be partitioned to enable the use of “lookup_local” function.