Cache placement policies

Not to be confused with cache replacement policies.

Cache placement policies are policies that determine where a particular memory block can be placed when it goes into a CPU cache. A block of memory cannot necessarily be placed at an arbitrary location in the cache; it may be restricted to a particular cache line or a set of cache lines[1] by the cache's placement policy.[2][3]

There are three different policies available for placement of a memory block in the cache: direct-mapped, fully associative, and set-associative. Originally this space of cache organizations was described using the term "congruence mapping".[4]

  1. ^ "The Basics of Cache" (PDF).
  2. ^ "Cache Placement Policies". Archived from the original on Feb 21, 2020.
  3. ^ "Placement Policies". Archived from the original on August 14, 2020.
  4. ^ Mattson, R.L.; Gecsei, J.; Slutz, D. R.; Traiger, I (1970). "Evaluation Techniques for Storage Hierarchies". IBM Systems Journal. 9 (2): 78–117. doi:10.1147/sj.92.0078.