allocates cache memory for Aggregator, Joiner, Lookup, Rank, and Sorter transformations in a mapping.
You can configure the cache sizes for these transformations. The cache size determines how much memory
Data Integration
allocates for each transformation cache at the start of a mapping run.
If the cache size is larger than the available memory on the machine,
Data Integration
cannot allocate enough memory and the task fails.
If the cache size is smaller than the amount of memory required to run the transformation,
Data Integration
processes some of the transformation in memory and stores overflow data in cache files. When
Data Integration
pages cache files to the disk, processing time increases. For optimal performance, configure the cache size so that
Data Integration
can process the transformation data in the cache memory.
By default,
Data Integration
automatically calculates the memory requirements at run time based on the maximum amount of memory that it can allocate. After you run a mapping in auto cache mode, you can tune the cache sizes for each transformation.