What is a memory cache-write-back?

What is a memory cache-write-back?

Memory cache-write-back is a caching technique used in computer systems where data is first written to the cache instead of directly to the main memory. The write-back process involves updating the cache with the modified data and marking it as dirty, while the corresponding data in the main memory remains unchanged. The actual write to the main memory is deferred until it is necessary, such as when the cache line is evicted or when a read operation requires the updated data. This technique helps reduce the number of memory writes, improving overall system performance by reducing memory access latency.