Skip to main content

Documentation Index

Fetch the complete documentation index at: https://docs.activeviam.com/llms.txt

Use this file to discover all available pages before exploring further.

JVM (Java Virtual Machine) tuning can help Atoti’s performance because the JVM manages memory allocation and garbage collection.
  • Avoids memory-related errors: Insufficient heap or off-heap memory can lead to OutOfMemoryError or failed data loads.
  • Reduces application pauses: Stop-the-world garbage collections can freeze the application during heavy workloads.
  • Improves stability: Balanced memory allocation prevents crashes caused by OS memory limits.

​
Which JVM memory areas does Atoti use?

​
Heap memory

  • Used for query execution.
  • Subject to garbage collection.
  • Grows and shrinks dynamically.

​
Off-heap memory

  • Stores most of the data structures of the cubes and datastores.
  • Not managed by garbage collection.
  • Must be explicitly sized.
performance-jvm-memory.png

​
When to tune JVM settings

JVM tuning is most effective when:
  • Large datasets require significant off-heap memory.
  • Frequent queries cause heavy heap usage.
  • Stop-the-world GCs impact performance during data loading or real-time updates.

​
Avoid excessive memory allocation

  • The sum of heap and off-heap memory must not exceed OS capacity.
  • Leave room for other processes to prevent JVM crashes.