Exceed onDemand A Technical Whitepaper

Exceed onDemand 5 — A Technical Whitepaper
A suspended session does not use a license. However, when a user resumes a suspended session,
he or she may consume one license based on the rules stated in Section 2: “Architecture.”
By default, when a session is in suspended mode, so are the X applications in that session. To maximize
the benefit of Suspend and Resume, some users may want to enable “Keep Suspended Session Active”
option so that the X applications continue to run on the proxy after the session is suspended.
However, not all sessions can be suspended. Exceed onDemand cannot suspend OpenGL sessions
due to technical restrictions. Users will not have the option of suspending such sessions.
Suspend on Disconnect (a.k.a. Crash and Resume)
Exceed onDemand is designed with mobility in mind. We understand that network inconsistency
and instability can occur and know the frustration it can cause. Based on the same principle and
mechanism as Suspend and Resume, Exceed onDemand extends the feature to safeguard any
non-OpenGL session. To enable this feature, users just have to turn on the “Suspend Disconnected
Session” option.
Figure 33 — Enable Suspend on Disconnect feature to safe guard your Exceed onDemand sessions
However, this feature comes at the expense of performance. As indicated in the previous chapter,
the Client is required to send the X session data to the Proxy as one of the steps in suspending a
session. But a crash is unpredictable by nature and will never give the Client time to send data to
the Proxy. To overcome this, the Proxy has to remain in a constant state of preparedness by keeping
track of all the information it sends to the desktop. The obvious side effect is the added work-load
and resource consumption on the host. But it may be a small price to pay for uninterrupted work
and to ensure that the mission critical applications are up and functional at all times.
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