When the DB2 HADR feature is enabled, the primary database's transaction logs are replicated to one or more standby databases in real time. The replication provides HA and DR protection, at a cost. The replication adds overhead to the primary's log writing.
This article sheds a little light on the inner workings of dynamic workload balancing of distributed connections, and how this can benefit the performance, scalability and availability of your DB2 for z/OS solutions.
When the term high availability is brought up, most DBAs reflexively think of technical solutions to help keep a system or database available for users – However, there is so much more to availability than simply ensuring that a database is available for a user to connect to.