Setting Runtime Memory

Doradus is generally stateless. Most of the memory it requires are for the following scenarios:

1.	Large update batches, which must be parsed and held in memory until written to the database.

2.	Queries that accumulate large result sets, which must be aggregated or sorted before returning.

3.	Immutable query results, such as OLAP query clauses and data arrays, which are cached on an LRU basis for “hot” data.

For most cases, Doradus is happy with 1 to 4 GB of memory. Since tests have shown that growing a Java process’s memory can be very disruptive, so set both the minimum and maximum memory parameters to the same value. Example:

java -Xms4G -Xmx4G -cp ... com.dell.doradus.core.DoradusServer