The driver uses connections in an asynchronous way. Meaning that multiple requests can be submitted on the same connection at the same time. This means that the driver only needs to maintain a relatively small number of connections to each Cassandra host. These options allow to control how many connections are kept exactly.
For each host, the driver keeps a core amount of connections open at all time (PoolingOptions#getCoreConnectionsPerHost). If the utilisation of those connections reaches a configurable threshold (PoolingOptions#getMaxSimultaneousRequestsPerConnectionTreshold), more connections are created up to a configurable maximum number of connections (PoolingOptions#getMaxConnectionPerHost). Once more than core connections have been created, connections in excess are reclaimed if the utilisation of opened connections drops below the configured threshold (PoolingOptions#getMinSimultaneousRequestsPerConnectionTreshold).
Each of these parameters can be separately set for
Assembly: Cassandra (in Cassandra.dll) Version: 220.127.116.11 (18.104.22.168)