Spare memory management in data storage device

A data storage device, comprising:

• means for storing data in a nonvolatile memory comprising a plurality of logical units (LUs) and a plurality of spare blocks (SBs), each of the plurality of LUs being allocated with one or more of the plurality of SBs;
• means for determining usage information of at least a first logical unit and a second logical unit of the plurality of LUs;
• and
• means for allocating, based on the usage information, a first spare block of the plurality of SBs associated with the first logical unit to the second logical unit in response to a depletion of the one or more of the plurality of SBs allocated to the second logical unit.

A data storage system, comprising:

• a host;
• and
• a data storage device connected to the host, comprising:
• a nonvolatile memory comprising a plurality of logical units (LUs) and a plurality of spare blocks (SBs), each of the plurality of LUs being allocated with one or more of the plurality of SBs;
• and
• a memory controller connected to the nonvolatile memory, the memory controller configured to:
• store data from the host in the nonvolatile memory;
• determine usage information of at least a first logical unit and a second logical unit of the plurality of LUs;
• and
• allocate, based on the usage information, a first spare block of the plurality of SBs associated with the first logical unit to the second logical unit in response to a depletion of the one or more of the plurality of SBs allocated to the second logical unit.