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Given the number of blocks in a set = the associativity factor = 8
Cache lines/blocks 2 9
6
Number of sets = = = 2 sets Chapter One: Computer architecture
Number of lines/blocks inaset 8
Number of bits in set number = 6
FOR ONLINE READING ONLY
32 bits
Tag Set Number Block/Line Offset
6 bits 6 bits
Figure 1.49: Number of sets in cache
(e) Number of bits in tag
Number of bits in tag = Number of bits in physical address – (Number of bits
in set number + Number of bits in block offset)
Number of bits in tag = 32 bits – (6 bits + 6 bits) = 20
32 bits
Tag Set Number Block/Line Offset
20 bits 6 bits 6 bits
Figure 1.50: Number of bits in the tag
Activity 1.12:
Exploring cache mapping techniques
Aim: To understand and apply different cache mapping techniques to
optimise data retrieval in computer systems
Materials: Computer, Internet, simulation tool(Such as Logisim), calculator or
spreadsheet
Instructions:
Explore different cache mapping techniques by calculating tag, set, and block
(or line) offsets. These calculations help locate specific data within the cache by
dividing the cache address into three parts: tag, set, and block/line offset.
The Challenge: Work with three common cache mapping schemes-Direct Mapped,
k-way Set Associative, and Fully Associative. For each scenario in Table 1.6, you
are given:
47
Student’s Book Form Five
Computer Science Form 5.indd 47 23/07/2024 12:32
