Two of the new features of Citrix XenApp 6.5 is the use of Session Pre-launch or Pre-start, which allows us to automatically start an ICA session for our users in order to avoid that small delay when they open the first app, the other new feature is the configuration of Session Linger or Persistent Session, which will allow setting a time for the ICA session to close when the user closes their last app, thus avoiding having to wait again when they open another app.

Session Pre-launch or Pre-start,
It should be considered that when the user starts an ICA session, they will be consuming a license.

First things, from Citrix AppCenter, About the application for users we are interested in enabling Pre-Launch for > “Other tasks” > “Create Pre-Launch application”,

On client machines (If we want to customize a client's machine): It can be enabled (1), Disabled (0) Or schedule the pre-launch by configuring it in the registry (Enabled by default), since: ‘HKEY_LOCAL_MACHINESOFTWARECitrixICA ClientPrelaunch’ Or ‘HKEY_CURRENT_USERSoftwareCitrixICA ClientPrelaunch’

In ‘State’: 0 – Disables pre-launch. 1 – Enables pre-launch on demand. 2 – Enables scheduled pre-launch (with HH:MM|L:M:X:J:V:S:D in ‘Schedule’).

View of a user with no apps open but with pre-launch enabled,

Session Linger or Persistent Session,

We can configure a delay when the user closes their last application, With two new policies, we can either disconnect a session or close it based on the time we configure (which by default is 0 minutes). It is configured through two policies in 'ICA'’ > 'Session Limits'.

Persistent session timeout interval: Ends an existing session after the specified number of minutes from when the last application is closed. If a new user application is started, the persistent session timeout is restarted. If it is not configured or set to zero, persistent session is disabled. This value can be any positive number.

Persistent session logoff timeout interval: Desconecta una sesión existente después de la cantidad de minutos especificada al salir de la última aplicación. Una vez desconectada, se libera la licencia de XenApp. Si el usuario inicia una aplicación antes de que caduque el intervalo del temporizador, se reiniciará el temporizador de desconexión de sesión persistente. Si no está configurado o si el valor es cero, las sesiones persistentes no se desconectarán antes de cerrar la sesión. This value can be any positive number.