Patent ID: 7580997
Filing Date: 2009-08-25
Classification: G06F

Abstract:
1. A method of recovering a modeled state of an entity in a distributed networked system following failure and recovery of an entity monitoring application, which said entity monitoring application comprises a counter, which said counter represents the modeled state of the entity in the system, comprising the steps of: (a) incrementing the counter in response to receiving an increment request to increment the state of the entity; (b) determining, in response to receiving a decrement request to decrement the state of the entity, if the decrement request is paired with an increment request received subsequent to the recovery of the entity monitoring application, and: if so, then decrementing the counter; and if not, then discarding the decrement request such that the decrement request has no effect on the counter; and (c) repeating steps (a) and (b) such that the modeled state of the entity converges with a true state of the entity as all decrement requests not paired with the increment request received subsequent to the recovery of the entity monitoring application are discarded; wherein the counter refers to a number of concurrent user sessions; wherein the counter is implemented in volatile memory; wherein the system comprises a plurality of entities and the entity monitoring application comprises a plurality of counters corresponding to the plurality of entities.