Write Policy
A cache’s write policy is a method that governs how and when data modifications are written to the main memory from the cache depending on its architecture. Write policies include:
The write-through policy, where data is written simultaneously to the cache and memory.
The write-back policy, where one bit of the tag (aka the block metadata) is allocated to storing a clean/dirty state to control which blocks must later be written into memory, grouping individual writes together at the expense of more logic.
Note!
When a cache miss occurs during a memory write, the cache always first writes the address block to itself from memory.