Memory system and operating method thereof

A data processing system, comprising:

• a memory device;
• a host including a cache memory;
• first and second buffers;
• and
• a controller suitable for controlling the memory device, the host, and the first and second buffers to perform a first buffering operation of buffering valid data of a victim block included in the memory device in the first buffer, a second buffering operation of buffering the valid data buffered in the first buffer in the second buffer, a caching operation of caching the valid data buffered in the second buffer in the cache memory, and a program operation of storing all the valid data of the victim block cached in the cache memory in target blocks included in the memory device,
• wherein the controller performs the first and second buffering operations and the caching operation on the valid data of the victim block in a pipelining scheme between the host and the first and second buffers.