Answer :
The concept being referred to in this question is related to computer architecture, specifically the handling of data between different levels of cache memory in a computer system.
Caches are used to temporarily store frequently accessed data to speed up retrieval times. Multilevel caches typically involve two or more layers, such as Level 1 (L1) and Level 2 (L2) caches. The inclusion property describes how data is managed between these levels.
Let's evaluate the options one by one:
A. L2 cache contains all data of L1.
- This option suggests that everything stored in L1 is also stored in L2, which aligns with the inclusion property. This is generally true for inclusive caches, where the higher-level cache (L2) contains all of the data of the lower-level cache (L1).
B. L1 and L2 are mutually exclusive.
- This would imply that there is no overlap between the contents of L1 and L2 caches, which describes an exclusive cache hierarchy instead of an inclusive one.
C. Data present in L2 is always in L1.
- This option is incorrect because, in an inclusive cache hierarchy, data present in L1 should also be present in L2, not vice versa.
D. Cache coherence is not needed.
- Cache coherence refers to the consistency of data stored in multiple cache locations, which is a separate topic from the inclusion property.
Given these explanations, the best description of the inclusion property in a multi-level cache is:
A. L2 cache contains all data of L1.
This reflects the traditional definition of an inclusive cache architecture.
