If you want to import mappings larger than 68 MB, import the mapping through command line for optimal performance. You can use the infacmd ipc ImportFromPC command to optimize import performance.

To improve performance during import from PowerCenter, you can add an option, -BlockSize to the infacmd ipc genReuseReportFromPC command.

Instead of importing every folder, you can import the required mappings from PowerCenter into the Model repository. Recommended Java heap size is 4 GB and blockSize is 100 for generating report especially if the user gets an out of memory error. You can also decrease the blockSize value in case of complex mappings.