In memory message store is a basic Message Store that stores messages in an in-memory queue. Since the messages are stored in an in-memory queue in case of a ESB profile restart, all the messages stored will be lost.
The in memory message store is lot faster than a persistent message store implementation, so it can be used to temporarily store messages for use cases such as the implementation of a high-speed store and forwarded pattern where message persistence is not a requirement.
In memory message stores are not recommended for use in production as well as in scenarios where large scale message storing is required. You can use an external message store (e.g., JMS message store) for such scenarios.
Following is the Add In Memory Message Store screen that you will see on the Management Console.
When you add an in memory message store, you need to specify a unique name for the message store.
For instructions on adding a required type of message store via the Management Console, see Adding a Message Store.
Following is a sample in memory message store configuration: