Memory system and operating method thereof

An operating method of a memory system comprising a first memory chip and a second memory chip, the operating method comprising:

• programming first data in both the first memory chip and the second memory chip in response to a program request for the first data so that the first data is stored in both the first memory chip and the second memory chip as same data;
• determining, in response to a read request for the first data, whether the first memory chip and the second memory chip are performing an operation for data different from the first data;
• and
• reading the first data from one of the first and second memory chips, upon determining that another one of the first and second memory chips is performing the operation for data different from the first data.

An operating method of a memory system comprising a plurality of memory chips, the operating method comprising:

• programming first data in a plurality of first memory chips among the plurality of memory chips, based on first importance of the first data, so that first data is stored in all of the plurality of first memory chips as same data;
• programming second data in only a single second memory chip among the plurality of memory chips, based on second importance of the second data;
• storing, in a first mapping table, a first physical address corresponding to at least one of the plurality of first memory chips having the first data stored therein;
• and
• storing, in a second mapping table, a second physical address corresponding to the single second memory chip having the second data stored therein.