BigMemory is an extension to Ehcache that enables you to create caches that reside outside the Java heap. Using BigMemory, you can create much larger caches than with local on-heap memory alone. You can use terabytes for caching, depending on the platform you use. Caches that you create using BigMemory also perform more predictably and consistently than on-heap caches, because they are not subject to the JVM garbage-collection process.