Scheduling operations in non-volatile memory devices using preference values

Abstract

A method of scheduling memory operations to be performed by non-volatile memory devices in a storage system includes identifying a plurality of memory operations to be performed by a plurality of non-volatile memory devices in the storage system. The number of memory operations in the plurality of memory operations is no greater than the number of non-volatile memory devices in the plurality of non-volatile memory devices; each memory operation is to be performed by a distinct non-volatile memory device; and the memory operations include host writes, garbage collection writes, and garbage collection reads. The method also includes, for each non-volatile memory device, assigning preference values to each of the memory operations. The method further includes assigning each memory operation to a distinct non-volatile memory device, using the preference values assigned to each of the memory operations for each non-volatile memory device.