"cluster" here is a thread pool used by the cassandra driver. We try to name them all but we must miss one in the tests as "cluster" is the default name of of the threads if you don't explicitly set one.

We should name it here:

Ideally we'd close it in only if the cluster has been used: https://github.com/akka/akka-persistence-cassandra/blob/master/core/src/test/scala/akka/persistence/cassandra/CassandraSpec.scala otherwise any test that hits that lazy val will need to do this.

However if you've verified this is the one that is leaked happy to merge this for now

Thanks for the detailed explanation. :)

I verified again. EventsByTagRestartSpec is the class that didn't close the driver.

I can change to:

session.getCluster.close()

I did notice

cluster.close()

We try to name them all

I am thinking of this:

  final override lazy val cluster = Cluster.builder()
    .addContactPoint("localhost")
    .withClusterName(this.getClass.getSimpleName)
    .withPort(port())
    .build()