GATE | Sudo GATE 2020 Mock I (27 December 2019) | Question 11
The size of the physical address space of a processor is 240 bytes. The capacity of cache memory is 512 Kbytes. The word length is 32 bytes. The size of each cache block is 16 words. For a 16-way set-associative cache memory, the length (in number of bits) of the tag field is _______________ .
Explanation: Given physical address space = 40 bits,
Cache memory size = 512 Kbytes = 219 bytes,
The word length is 32 bytes, and size of each cache block is 16 words. So, word offset is
= 32*16 bytes = 512 bytes = 29 bytes
Line offset is,
= 219 bytes / 29 bytes = 210
So, set offset is,
= 210 / 16 = 210 / 24 = 26 = 6 bits
Hence, the length (in number of bits) of the tag field is,
= 40 - 6 - 9 = 25 bits
Option (D) is correct.
Quiz of this Question
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