--- schema_version: "1" id: c60d5b277b881b0d3e8a8486bc9273a5f1fcc79bb14761a57b31ac14e0b421c6 title: Tune JMS Connector for Performance collection: mulesoft version: current locale: en-us portal_url: https://docs.salesforce.com/mulesoft/current/en-us/jms-connector/latest/jms-performance.md canonical_url: https://docs.mulesoft.com/jms-connector/latest/jms-performance source_site: docs.mulesoft.com content_type: documentation content_hash: c0dabb7f2f5f058ef15374c9bfdc3278ee315e5545ee33ed86b6515383cf6244 description: MuleSoft Documentation Site release: "2.0" latest: true --- --- product: JMS Connector version: 2.0 is-latest-version: true keywords: jms, connector, consume, message, source, listener --- # Tune JMS Connector for Performance > For the full documentation index, see: https://docs.mulesoft.com/llms.txt Performance is sometimes negatively impacted by message . The following recommendations can help you get the most of Anypoint Connector for JMS (JMS Connector) for your Mule applications. ## Connections Caching Reuse Because connections are expensive to create, reuse them as much as you can. By default, JMS Connector uses a caching strategy that reuses as many consumers and producers as possible. To avoid performance degradation, do not disable connection caching. ## Increased Concurrent Messages Processing To improve the performance of your application, increase the number of consumers that receive messages from the same destination. JMS Connector enables you to increase the number of consumers by configuring the **Number of consumers** field in the **On New Message** source. By default, this source enables four consumers to receive messages concurrently on the same destination, but you can increase this number to the one that best fits your needs. In the following example, you increase the number of consumers receiving messages concurrently: 1. In Studio, select the **On New Message** source from your flow. 2. In the **On New Message** source configuration screen, set the **Number of consumers** field to `20`. ![In the On New Message configuration screen](/mulesoft/current/en-us/jms-connector/latest/_images/jms-performance-1.png) Figure 1. JMS Connector Number of consumers Configuration In the XML editor, the `numberOfConsumers` configuration looks like this: ```xml ``` ## Cluster Configuration Optimization For applications running in clusters, consider the primary node and how the connector behaves. When the app runs in a cluster, the **On New Message** source default behavior receives messages only in the primary node, no matter what kind of destination the app consumes. When consuming messages from a queue, the default connector behavior is to receive messages in all the cluster’s nodes, not just the primary node. JMS Connector enables you to configure the **Primary node only** field in the **On New Message** source. When the connector consumes from a queue in a cluster, do not select the **Primary node only** field, which defaults to `false`. In the following example, you configure the connector to receive messages in all the nodes: 1. In Studio, select the **On New Message** source from your flow. 2. In the **Advanced** tab, leave unselected the **Primary node only** field. ![In the Advanced tab of the On New Message source](/mulesoft/current/en-us/jms-connector/latest/_images/jms-performance-2.png) Figure 2. JMS Connector Primary Node only Configuration In the XML editor, the `primaryNodeOnly` configuration looks like this: ```xml ``` When consuming messages from a topic, the default connector behavior is to receive messages only in the primary node, which avoids processing the same message multiple times across the cluster. When consuming messages from a topic in a cluster, the configuration of **Primary node only** unselected causes the cluster to process the same message more than once, unless you also configure shared subscriptions. If you are using the JMS 2.0 shared subscriptions mechanism, then change the cluster configuration to consume from all the nodes, again setting the **Primary node only** field to `false`. In the following example, you configure the connector using 2.0 spec shared-subscriptions mechanism: 1. In Studio, select the **On New Message** source from your flow. 2. In the **On New Message** source configuration screen, select **Topic consumer**. 3. Select the **Shared** option. 4. Set the **Subscription name** to `clusteredEventListener`. 5. In the **Advanced** tab, leave unselected the **Primary node only** field. ![In the Advanced tab of the On New Message source](/mulesoft/current/en-us/jms-connector/latest/_images/jms-performance-3.png) Figure 3. JMS Connector Primary Node only Configuration In the XML editor, the `jms:topic-consumer`, `shared`, and `primaryNodeOnly` configurations look like this: ```xml ``` ## Configure Prefetch for JMS Connector For JMS Connector, when using ActiveMQ client, you configure prefetch on the server connection URL. Refer to the [ActiveMQ documentation](https://activemq.apache.org/components/classic/documentation/what-is-the-prefetch-limit-for#:~:text=Specifying%20the%20PrefetchPolicy) for details. For example, consider these connection URLs with the `jms.prefetchPolicy.all` parameter: ```xml tcp://localhost:61616?jms.prefetchPolicy.all=50 tcp://localhost:61616?jms.prefetchPolicy.queuePrefetch=1 ``` In the JMS Connector XML configuration, the configuration of the connection `brokenUrl` looks like this: ```xml ``` Increase prefetch values for high performance with high message volumes. However, for lower message volumes, where each message takes a long time to process, set the prefetch to `1`. This ensures that a consumer is only processing one message at a time. Specifying a prefetch limit of zero, however, causes the consumer to poll for messages, one at a time, instead of the message being pushed to the consumer. ## See Also - [Consume Messages](https://docs.mulesoft.com/jms-connector/latest/jms-consume) - [Configure Topic Subscriptions](https://docs.mulesoft.com/jms-connector/latest/jms-topic-subscription)