Data storage device and operating method thereof

A method of operating a data storage device, the data storage device including a non-volatile memory device configured to store a plurality of L2P entries related to a plurality of logical addresses, and a controller configured to control the non-volatile memory device, the method comprising:

• receiving by the controller a read request and read logical address information from a host device;
• determining by the controller whether a sequential flag related to at least one sequential segment corresponding to the read logical address information is a set state or not based on a sequential flag table in a random access memory;
• reading by the controller a part of L2P entries corresponding to the read logical address information when the sequential flag is the set state;
• and
• loading by the controller the read L2P entries into the random access memory,
• wherein each of the sequential segments including at least one logical address, and
• wherein the sequential flags are flags representing whether physical addresses corresponding to the logical addresses in each of the sequential segments are sequential or not.

A memory system comprising:

• a memory device configured to store a plurality of logical-to-physical (L2P) entries;
• and
• a controller configured to:
• control the memory device to load therefrom, in response to a sequential read request provided along with consecutive logical addresses respectively corresponding to consecutive physical addresses of the memory device, a L2P entry corresponding to a reference logical address among the consecutive logical addresses;
• and
• translate the consecutive logical addresses into the consecutive physical addresses through the L2P entry having the reference logical address and the consecutiveness of the logical and physical addresses.