Verifying the available disk space

Ensure the stability and availability of a Cassandra deployment on Pega Platform by providing enough disk space to run compactions.

To run compactions without errors, ensure that you have at least 60% free disk space.
  1. In the header of Dev Studio, click Configure > Decisioning > Infrastructure > Services > Decision Data Store.
  2. On the Decision Data Store landing page, click the status of the node for which you want to check the available disk space.
  3. In the Disk usage section, verify that the amount of existing data constitutes less than 40% of the total disk space.
    The amount of data shown in the Disk usage section refers to data in SSTables, and does not include the disk space that Cassandra uses for compaction.
  4. If the existing data takes up more than 40% of the total disk space, provide Cassandra with more disk space by removing obsolete files, or by adding more disk space.
    To remove obsolete Cassandra files, in the nodetool utility, run the nodetool cleanup command. For more information about adding additional disk space, see the Apache Cassandra documentation.