Abstract: An inflight-I/O-based storage emulation system includes a storage emulation device coupled to host devices, and to storage devices that provide primary, secondary, and metadata storage systems. The storage emulation device stores I/O commands directed to the primary storage system by the host devices in its I/O queue. If the storage emulation device predicts I/O operations for I/O commands in its I/O queue do not exceed a threshold, it executes at least some of those I/O commands to store first data in the primary storage system. If the storage emulation device predicts I/O operations for I/O commands in its I/O queue exceed the threshold, it executes at least some of those I/O commands to store second data in the secondary storage system, and provides mapping information in the metadata storage system that identifies storage location(s) in the primary storage system associated with the second data in the secondary storage system.

Abstract: An inflight-I/O-based storage emulation system includes a storage emulation device coupled to host devices, and to storage devices that provide primary, secondary, and metadata storage systems. The storage emulation device stores I/O commands directed to the primary storage system by the host devices in its I/O queue. If the storage emulation device predicts I/O operations for I/O commands in its I/O queue do not exceed a threshold, it executes at least some of those I/O commands to store first data in the primary storage system. If the storage emulation device predicts I/O operations for I/O commands in its I/O queue exceed the threshold, it executes at least some of those I/O commands to store second data in the secondary storage system, and provides mapping information in the metadata storage system that identifies storage location(s) in the primary storage system associated with the second data in the secondary storage system.