CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority under 35 U.S.C. § 119(a) to Korean Application Number 10-2020-0061334, filed on May 22, 2020, in the Korean Intellectual Property Office, which is incorporated herein by reference in its entirety.

BACKGROUND

1. Technical Field

Various embodiments generally relate to a storage device, and more particularly, to a storage device and an operating method thereof.

2. Related Art

In recent years, the paradigm for computer environments has shifted to ubiquitous computing in which computer systems may be used anytime and anywhere. As a result, the use of portable electronic apparatuses such as mobile phones, digital cameras, and laptop computers has been increasing rapidly. Generally, portable electronic apparatuses use data storage devices that employ memory devices. Data storage devices may be used to store data used in the portable electronic apparatuses.

Data storage devices using memory devices have no mechanical driving units and thus exhibit good stability and endurance, fast information access rates, and low power consumption. Such data storage devices include a universal serial bus (USB) memory device, a memory card having various interfaces, a universal flash storage (UFS) device, a solid state drive (SSD), and the like.

SUMMARY

Embodiments are provided to technology capable of preventing performance from being deteriorated and improving spatial efficiency and an operating method thereof.

In an embodiment of the present disclosure, a storage device may include: a nonvolatile memory including a plurality of first blocks having memory cells each configured to store one bit of data and a plurality of second blocks having memory cells each configured to multiple bits of data; and a controller configured to determine whether or not a number of use-completed second blocks, each of which has a first threshold number or less of valid pages, among use-completed second blocks of the plurality of second blocks, is equal to or larger than a second threshold number and to select, according to a determination result, a victim block on which garbage collection is to be performed among used-completed first blocks of the plurality of first blocks or the use-completed second blocks each having the first threshold number or less of valid pages.

In an embodiment of the present disclosure, an operating method of a storage device which includes a nonvolatile memory including a plurality of first blocks having memory cells each configured to store one bit of data and a plurality of second blocks having memory cells each configured to store multiple bits of data and a controller configured to control the nonvolatile memory, the method may include: determining whether or not a garbage collection trigger condition for the nonvolatile memory is satisfied; determining whether or not a number of use-completed second blocks, each of which has a first threshold number or less of valid pages, among use-completed second blocks of the plurality of second blocks, is equal to or larger than a second threshold number; and selecting, according to a determination result for the number of use-completed second blocks, a victim block on which garbage collection is to be performed among used-completed first blocks of the plurality of first blocks or the use-completed second blocks each having the first threshold number or less of valid pages.

In an embodiment of the present disclosure, a storage device may include: a nonvolatile memory including a plurality of single-level cell (SLC) blocks and a plurality of extra-level cell (XLC) blocks; and a collector configured to select a victim block on which garbage collection is to be performed among the plurality of SLC blocks or among the plurality of XLC blocks, based on a number of use-completed XLC blocks each having K or less valid pages among use-completed XLC blocks of the plurality of XLC blocks, wherein K is a natural number of 1 or more.

In an embodiment of the present disclosure, a storage device may include: a nonvolatile memory including a plurality of first blocks having memory cells each configured to store one bit of data and a plurality of second blocks having memory cells each configured to store multiple bits of data; a volatile memory configured to store valid pages in use-completed second blocks each of which has a first threshold number or less of valid pages, among the plurality of second blocks; and a controller configured to determine whether or not the number of use-completed second blocks each having the first threshold number or less of valid pages is greater than or equal to a second threshold number and select, according to a determination result, a victim block on which a garbage collection is to be performed among used-completed first blocks of the plurality of first blocks or the use-completed second blocks each having the first threshold number or less of valid pages.

According to embodiments, write speed may be increased by performing garbage collection (that is, migration) on the SLC block until the number of XLC blocks having a valid page equal to or less than a determined value becomes a determined value or more and when the number of XLC blocks having the valid page equal to or less than the determined value is the determined value or more, the number of free blocks may be maintained at a constant level by performing garbage collection on the XLC block. According to the present embodiments, the deterioration of the write performance in the storage device may be prevented and simultaneously the free blocks of a constant number or more may be continuously maintained.

These and other features, aspects, and embodiments are described in more detail below.

