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It is not recommended to cluster session controllers to obtain better performance, usually having two session controllers for fail-over purposes is more than enough. Testing has proved that there is little or no gain in performance by having more than one session controller. The CPU usage of the PP server is only in very few installations above 20%. So most likely adding additional machines or session controller instances, often only generates more session replication, and does not improve overall performance.
What
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Works and What Does Not
First of all, keep things simple – there is no reason to set up 10 different PP servers in a cluster, if 2 is enough – having too many servers just complicates the configuration needlessly, and increases the risk that something will go wrong.
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