Product Administration › Data Collector Caching of Polled Data When the Data Aggregator Host is Unavailable › Modify the Data Cache Memory Limit

Modify the Data Cache Memory Limit

You can modify the amount of data that Data Collector caches when Data Aggregator is unavailable.

Follow these steps:

1. Calculate the amount of memory that is required for data caching.
2. Make a note of the amount of memory that is required for data caching.
3. Log in to the computer where Data Collector is installed. Log in as the root user or a sudo user with access to a limited set of commands.

   Note: For more information about the sudo user, see the Data Aggregator Installation Guide.

4. Stop Data Collector using this command:

   service dcmd stop
   

5. Modify the IM_MAX_MEM memory setting for Data Collector:
   1. Access the Data Collector installation directory/apache-karaf-2.3.0/jms/local-jms-broker.xml file.
   2. Change the IM_MAX_MEM limit to two times the value you noted in step 2. Verify that this value is not more than the available RAM on the system.
6. Modify the cache memory limit for the JMS broker on Data Collector:
   1. Access the Data Collector installation directory/apache-karaf-2.3.0/jms/local-jms-broker.xml file.
   2. Locate the following line:

      <memoryUsage limit=”value”/>
      

      value

      Is the current cache limit setting.

   3. Modify the current cache limit setting with the value that you calculated previously and save the file.
7. Make Data Collector aware of the changes to the jms/local-jms-broker.xml file. Type the following command to deploy a fake .lock file. A fake .lock file makes Data Collector think that there was an ungraceful shutdown:

    echo `date` > /opt/IMDataCollector/apache-karaf-2.3.0/.lock
   

8. Restart Data Collector using this command:

   service dcmd start
   

   The cache memory limit is configured.