5250 Connect User’s Guide
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Maximizing Performance with the Logon Component
The Logon Actions must be structured properly and therefore always begin and
end with a Map Screen Action as shown in the screen below.
The final Map Screen action in the Logon block guarantees that control is not
turned over to the 5250 Component before the screen of interest has arrived in the
connection. Without this, the 5250 Component could start at an invalid screen,
throw an exception, and possibly corrupt a transaction. It is not necessary for the
Map Screen to contain any actions, per se, but it is critical that the Map Screen
prevents control being passed to the 5250 Component prematurely. It also
performs a field count check on the screen when it arrives to make sure it is the
same screen captured during the initial recording session.
NOTE: You may notice when animating a Logon Component that the ending Map
Screen is skipped. This is normal design-time behavior. In a production
environment , the actions in a Logon Component always execute in an interleaved
manner with a 5250 Terminal component. Animating a Logon Component from
start to finish actually creates an abnormal sequence of events that would result in
two Map Screens being processed in succession, which is not allowed.
The performance benefit comes into play as a result not only of connection reuse
but launch-screen reuse. For example, if a User ID pool of three entries is fully
used and (ultimately) reused by the execution of a component fifteen times, the
overhead of navigating to a menu item that executes the transaction of interest will
occuro nly three times. Likewise, there will only be three logons to the host
because the Logon actions at the top of a Logon Component are executed only
once—when a new connection is activated (not when it is reused). This is key to
obtaining maximum performance in a high-transaction-volume production
settings.
