Patent ID: 8635208

Claim:
A system comprising: at least one processor; and a non-transitory computer-readable storage medium comprising instructions stored thereon that, when executed by at least one processor, are configured to cause the system to implement: a request handler configured to: determine a query of a data stream management system (DSMS), the query currently being executed using stored stream data within a buffer associated with the query, the stored stream data being received from at least one data source and being removed from the buffer in association with new stream data being received, wherein the stored stream data includes at least one original window of state data from the stream data; and determine a new query having at least first new window, a second new window, and a third new window corresponding to the at least one original window of the query; a windows sorter configured to cause the system to sort the first, second, and third new windows from longest duration to shortest duration, the first new window having the longest duration and the third new window having the shortest duration; and a migration estimator configured to: calculate a first reduced window size for the second new window based on new state data values collected during a transfer of new state data values associated with the first window; calculate a second reduced window size for the third new window based on new state data values collected during the transfer of new state data values associated with the first window and a transfer of new state data values associated with the second window; and calculate at least a first migration time for the first new window, a second migration time for the first reduced window size for the second new window, and a third migration time for the second reduced window size for the third new window, the first, second, and third migration times being times for migrating state data from the at least one original window to the first new window, the second new window, and the third new window.