Efficient Implementation of Optimized Host-Based Garbage Collection Strategies Using Xcopy and Arrays of Flash Devices

摘要

A method of managing a storage system having one or more storage devices includes a host-based garbage collection operation that includes identifying a logical stripe in accordance with data storage information stored at the host system, and enabling a process of coalescing valid data in a target logical stripe, the coalescing process including moving the valid data in the logical stripe and repacking valid logical addresses to the beginning of the target logical stripe, comprising the identified logical stripe or another logical stripe. Further, the use of an internal copy operation allows the host-based garbage collection operation to occur without transferring data back to the host, thus minimizing the number of I/O operations between the host and storage devices. Additionally, use of the host-based garbage collection operation allows device-level garbage collection to be minimized, and more sophisticated garbage collection algorithms (e.g., matching the current workload) to be used.