The JVM Argument in PDN article above is meant only for issues specific to a high native memory footprint / Native memory exhaustion. However, you use case indicate that this a Heap memory exhaustion from loading a lot of work data into the Clipboard from the ReportDef call. On What application server are you running? If you are on IBM Websphere, can you share the generated JavaCore dump (javacore.txt) during the OOMError. Also share the JVM (SystemOut) and Pega logs (PegaRULES and PegaRULES-ALERT) for a quick review.