Patent ID: 8566281
Filing Date: 2013-10-22
Classification: G06F

Abstract:
1. A method for implementing multi-array consistency groups using a write queuing mechanism, comprising: applying a write Input/Output (I/O) queue interval to a Logical Unit (LU) member of a consistency group (CG), wherein a storage array where the LU member of the CG resides being a participating storage array, wherein the applying includes queuing write I/Os in a First-In-First-Out (FIFO) order; marking each write I/O with a timestamp; suspending I/O from the participating storage array to the LU member of the CG upon the participating storage array receiving a snapshot request from a master storage array, the snapshot request having a snapshot request timestamp; determining a roundtrip latency between at least two participating storage arrays of the CG through an exchange of a pair of test messages; determining a minimum time interval of the write I/O queue interval using the roundtrip latency; and determining whether the snapshot request timestamp is within the write I/O queue interval of the participating storage array based at least on the minimum time interval of the write I/O queue interval, wherein when the snapshot request timestamp is determined to be within the write I/O queue interval of the participating storage array, the participating storage array performs at least one of: