How do I increase the Memory Usage limit of MEDC?

At peak usage (patching 100 servers or so at a time), the CPU is pegged at 100%, which is good and expected, and the network is pushing 500-600Mb, but the memory stands firm at 6.5GB used of 16GB RAM available, and the top file I/O in Perfmon is the pagefile,sys.  This suggests a memory shortage when the MEDC app and machine is using less than half available actual memory.

I would like to raise this memory cap and improve MEDC application performance.  Where is this parameter, and how do I adjust it?  Thank you.