User Guide
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Tuning the JVM Memory Settings

To achieve optimal performance for your cluster size, you may need to increase the JVM memory settings.

The default setting, 2048 MB, is appropriate for a cluster with up to 100 nodes. For each additional 100 nodes, increase this setting by 0.5 GB to improve performance.

To adjust the setting, in the Ambari Web UI, navigate to the SmartSense service's Config section > Advanced > Advanced hst-server-conf where you will find the Server max heap size configuration property.