Patent ID: 6542974
Filing Date: 2003-04-01
Classification: G06F

Abstract:
A data storage facility with first and second data stores means, and a buffer means in which first and second data processes manipulate common data comprising:A) pending write controller means responsive to a write request from a data process for identifying a specific location being transferred to said buffer means as a pending write request with the data associated with the pending write request thereafter being transferred to the specific location at a corresponding data store, B) means for establishing a first operating mode during which the second data store means acts as a mirror for the first data store means that interacts with the first data process, C) operating mode means for transferring the operation of the storage facility from the first operating mode to a second operating mode during which said second data store means interacts with the second data process and ceases to act as mirror for said first data store means, and D) control means for controlling the processing of all pending write requests during the second operating mode at the time said operating mode means effects the transfer to the second operating mode, said pending write request controller means operating in parallel with and transparently to the interaction between the first and second data store means with the first and second data processes, respectively.