When the PowerCenter Integration Service process creates memory cache, it also creates cache files. The PowerCenter Integration Service process creates cache files for the following mapping objects:
Aggregator transformation
Joiner transformation
Rank transformation
Lookup transformation
Sorter transformation
XML target
By default, the DTM creates the index and data files for Aggregator, Rank, Joiner, and Lookup transformations and XML targets in the directory configured for the $PMCacheDir service process variable. The PowerCenter Integration Service process names the index file PM*.idx, and the data file PM*.dat. The PowerCenter Integration Service process creates the cache file for a Sorter transformation in the $PMTempDir service process variable directory.