The disclosure is related to balancing resources between pools of servers, e.g., by moving servers from a first pool of servers to a second pool of servers. The first pool executes a first version of an application, e.g., a desktop version, and the second pool executes a second version of the application, e.g., a mobile version. The technology moves a number of servers from an “OK” pool to a “not OK” pool. A “not OK” pool is a pool whose performance metric, e.g., response latency of a server, does not satisfy a criterion, and an “OK” pool is a pool whose performance metric satisfies the criterion even if the number of servers are removed from the pool. The number of servers to be moved is determined as a function of the increase in load which the pool can withstand by remaining in OK state even after the servers are removed.