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General Configuration Dialog Box

Use the options in the General Configuration dialog box to specify the criteria that the pool will use for session allocation and thread management. The values you select on this page depend on your particular system needs and the intended use of your session pool.

To display the General Configuration dialog box, in the Server pane, select a server and choose Configure. On the Pools page, select a pool and choose General Configuration. This dialog box is also displayed as part of the process when you create a new pool.

Note To change most configuration options, you must stop the pool in order for the options to be available. To stop a pool, choose Monitor in the left pane of the MCS window, and then choose the Pools page. Select the pool you want to edit, and then choose Change State.

Initial Sessions: Specify the number of sessions that will be created at pool startup. For each session that is created, a connection is made to the host. For example, you may want to set this for a large number if you anticipate a large number of people executing transactions when the pool is first started.

Maximum Sessions: The maximum number of sessions that can exist at any one time and will often equal the number of IDs available to the sessions in a pool. This number could be limited by memory or other machine resource constraints.

Minimum Free Sessions: The minimum number of free sessions that should be available for the next request that comes in. This setting differs from the selected number of initial sessions since the initial sessions are the sessions available to you at startup, while the number of minimum free sessions is the number that will be kept continuously available. For example, you may require 200 initial sessions for the initial morning rush, but keep only ten extra free sessions available throughout the remainder of the day.

This setting will not cause the pool to exceed the number of Maximum Sessions that you set.

Connections that are inactive for a set time period are shutdown and removed from the pool. You can set this host inactivity timeout value on the Connection Configuration page.

Maximum Free Sessions: The maximum number of sessions that can be available for use at any one time. This setting should be used to limit resource use. The pool will adjust itself down to this level.

Automatically Start Pool: When selected, each pool will start automatically when the Runtime Service starts. This option is selected by default. To require a pool to be manually started or stopped, clear the check box.

If you set up start and stop times for a pool using the pool scheduler, those settings will automatically start and stop the pool according to the schedule you set. See the Related Topic, Creating Pool Schedules for instructions on setting up an automatic timetable.

Optimized Mode: When selected, you can increase the maximum number of host connections and the speed of network communication with the host. This feature is available only if Java 2 Standard Edition (J2SE) 1.4 is installed. If enabled, all IBM 3270 connections will use optimized mode. This option is cleared by default.

There are a few limitations that may arise when using optimized mode.

Monitoring Threads: Monitor threads keep track of the number of available connections and those that are in use. Monitor threads are created when you start the pool and exist until the pool is stopped. The maximum value you can select for this option is 25. The default value is the value that is specified on the Session Pooling Configuration page.

Initialization Threads: Pool initialization threads exist only when you start or stop a pool. Each thread can initialize one connection at a time. Depending on the number of connections you create, the higher the number you set here, the more quickly your pool starts or stops. The maximum value you can select for this option is 25. If the host starts to refuse connections, lower the number of initialization threads for the pool. The default value is the value that is specified on the Session Pooling Configuration page.

For more informaton on heap size and memory options, see Changing Runtime Service Options.

Related Topics
bullet Creating Pool Schedules
bullet Changing Runtime Service Options
bullet Creating Session Pools
Related Topics Configuring Your Run-time Environment, Overview
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