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It is possible to set a limit to the number of service instances that are maintained in the system at any given time. It is done by setting the min_app_instances parameter parameter for any service cluster and the autoscaler will ensure that the system will not scale down below that even though there is no considerable service requests in-flight.
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The user can set the max_app_instances parameter for any service cluster to control the number of instances that the autoscaler can start. The autoscaler ensures that the system will not scale up above the limit specified even though there is a high load of requests in-flight. When you pay for the instances that you start-up it it is very useful to set the max_app_instances parameter .
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