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As the mapping becomes set associative, the complexity reduces, but so does the fl exibility.
For any system, the chosen mapping technique will be a compromise between these two con-
fl icting factors.
12.6.4 | Cache Write Policies
Remember that a cache contains a copy of some part of the content of main memory. When a
block of data is brought into the cache from main memory and processed, that content could get
changed. However, the original content in main memory does not get changed. is will create
an inconsistency, and to avoid it, the main memory content should be correspondingly changed.
For this, caches have what is called a ‘write policy’.
For any cache, polices regarding reading and writing are pre-defi ...