User's Manual

Logon Components,Connections and Connection Pools

Maximizing Performance with Keep Alive Actions

Map Screens must also be processed at the beginning and end of the Keep Alive

section.

Not only does the Keep Alive section prevent the connection from closing, but it

must make sure that the proper launch screen is present when the execution is

completed. Therefore, the first Map Screen checks to make sure that during the

time the connection was available but not in use, that an unexpected screen didn’t

arrive from the host. The ending Map Screen prevents the premature release of the

connection to the next 5250 Component. See below for a typical Keep Alive

actions block.

Logoff Actions

Logoff actions essentially navigate the User ID properly out of the host system

after a timeout.

Logoff actions execute once for a given connection and only when a connection

times out (i.e. the Inactivity Lifetime expires) or the connection is closed via the

5250 Server console.

In a “best practices” sense, it’s vitally important to make Logoff Actions

bulletproof. If an exception occurs during execution of the Logoff actions, exteNd

Composer will break its connection with the host, freeing the UserID in the pool.

But the UserID may still be active on the host. Until the host kills the UserID (from

inactivity), a subsequent attempt by the pool to log on with that UserID may fail,

unless you’ve coded your logon to handle the situation. Logon failures cause the

UserID to be discarded from the pool, reducing the potential pool size and

performance overall. As with Logon and Keep Alive actions, the way to guarantee

you are on the proper screen at the end of the logoff is to end with a Map Screen.