1. A method for efficient thresholding of nonvolatile storage (NVS) for a plurality of types of storage rank groups by a processor, comprising: determining each target storage device in a pool of target storage devices as one of a hard disk drive (HDD) and a solid state drive (SSD) device, the each target storage device classified into one of a SSD rank group, a Nearline rank group, an Enterprise rank group, and an Ultra-SSD rank group in the pool of target storage devices, wherein the Nearline rank group and the Enterprise rank group comprise a HDD rank group, and the Nearline rank group, the Enterprise rank group, and the SSD rank group comprise the Non-Ultra-SSD rank group; and adjusting thresholds for preventing space allocation in the NVS for at least one of the classified target storage devices based on one of the presence and absence of identified types of the classified target storage devices.