Sun Microsystems 820434310 manual Tunable ORB Parameters, ORB Thread Pool Parameters

ORB Settings

TABLE 3–3Tunable ORB Settings	(Continued)
RMI/ IIOP from ORB to Enterprise Server		communication	steady-thread-pool-size, max-thread-pool-size,
		infrastructure, thread	idle-thread-timeout-in-seconds
		pool
RMI/ IIOP from a vendor ORB		parts of communication	steady-thread-pool-size, max-thread-pool-size,
		infrastructure, thread	idle-thread-timeout-in-seconds
		pool
In-process		thread pool	steady-thread-pool-size, max-thread-pool-size,
			idle-thread-timeout-in-seconds

Tunable ORB Parameters

Tune the following ORB parameters using the Admin Console:

■Thread Pool ID: Name of the thread pool to use.

■Max Message Fragment Size: Messages larger than this number of bytes will be fragmented. In CORBA GIOPv1.2, a Request, Reply, LocateRequest and LocateReply message can be broken into multiple fragments. The first message is a regular Request or Reply message with more fragments bit in the flags field set to true. If inter-ORB messages are for the most part larger than the default size (1024 bytes), increase the fragment size to decrease latencies on the network.

■Total Connections: Maximum number of incoming connections at any time, on all listeners. Protects the server state by allowing finite number of connections. This value equals the maximum number of threads that will actively read from the connection.

■IIOP Client Authentication Required (true/false)

ORB Thread Pool Parameters

The ORB thread pool contains a task queue and a pool of threads. Tasks or jobs are inserted into the task queue and free threads pick tasks from this queue for execution. Do not set a thread pool size such that the task queue is always empty. It is normal for a large application’s Max Pool Size to be ten times the size of the current task queue.

The Enterprise Server uses the ORB thread pool to:

■Execute every ORB request.

■Trim EJB pools and caches.

Thus, even when one is not using ORB for remote-calls (via RMI/ IIOP), set the size of the threadpool to facilitate cleaning up the EJB pools and caches.

Set ORB thread pool attributes under Configurations > config-name> Thread Pools > thread-pool-ID, where thread-pool-ID is the thread pool ID selected for the ORB. Thread pools have the following attributes that affect performance.

72 Sun GlassFish Enterprise Server 2.1 Performance Tuning Guide • January 2009