Thread pooling for RMI connection handlers

When a client connects to the server socket, a new thread is forked to deal with the incoming call. The IBM® SDK implements thread pooling in the sun.rmi.transport.tcp.TCPTransport class.

Thread pooling is not enabled by default. Enable it with this command-line setting:

 -Dsun.rmi.transport.tcp.connectionPool=true

Alternatively, you could use a non-null value instead of true.

With the connectionPool enabled, threads are created only if there is no thread in the pool that can be reused. In the current implementation of the connection Pool, the RMI connectionHandler threads are added to a pool and are never removed. Enabling thread pooling is not recommended for applications that have only limited RMI usage. Such applications have to live with these threads during the RMI off-peak times as well. Applications that are mostly RMI intensive can benefit by enabling the thread pooling because the connection handlers will be reused, avoiding the additional memory usage when creating these threads for every RMI call.