Storing Tables in Off-Heap Memory

GemFire XD supports storing table data directly in the JVM heap (the default), or in off-heap memory, which refers to memory that is not part of the JVM's allocated heap. Storing table data in off-heap memory enables you to scale your very large databases in-memory, while improving CPU utilization and avoiding the pauses caused by JVM garbage collection.

By storing your table data into off-heap memory, it is possible to see a performance improvement of 30% due to less CPU time spent on garbage collection. Typically, you decide whether to store your table in off-heap memory after you have completed initial development, iterated over several schema versions and when you begin working with much larger data sets.