1
GATE CSE 2022
MCQ (More than One Correct Answer)
+1
-0.33

Let WB and WT be two set associative cache organizations that use LRU algorithm for cache block replacement. WB is a write back cache and WT is a write through cache. Which of the following statements is/are FALSE?

A
Each cache block in WB and WT has a dirty bit.
B
Every write hit in WB leads to a data transfer from cache to main memory.
C
Eviction of a block from WT will not lead to data transfer from cache to main memory.
D
A read miss in WB will never lead to eviction of a dirty block from WB.
2
GATE CSE 2022
MCQ (More than One Correct Answer)
+1
-0.33

Consider a system with 2 KB direct mapped data cache with a block size of 64 bytes. The system has a physical address space of 64 KB and a word length of 16 bits. During the execution of a program, four data words P, Q, R, and S are accessed in that order 10 times (i.e., PQRSPQRS .....). Hence, there are 40 accesses to data cache altogether. Assume that the data cache is initially empty and no other data words are accessed by the program. The addresses of the first bytes of P, Q, R, and S are 0$$\times$$A248, 0$$\times$$C28A, 0$$\times$$CA8A, and 0$$\times$$A262, respectively. For the execution of the above program, which of the following statements is/are TRUE with respect to the data cache?

A
B
Once P is brought to the cache it is never evicted.
C
At the end of the execution only R and S reside in the cache.
D
3
GATE CSE 2021 Set 2
Numerical
+1
-0
Consider a set-associative cache of size 2 KB (1 KB = 210 bytes) with cache block size of 64 bytes. Assume that the cache is byte-addressable and a 32-bit address is used for accessing the cache. If the width of the tag field is 22 bits, the associativity of the cache is _______
4
GATE CSE 2020
Numerical
+1
-0.33
A direct mapped cache memory of 1 MB has a block ize of 256 bytes. The cache has an access time of 3 ns and a hit rate of 94%. During a cache miss, it takes 20 ns to bring the first word of a block from the main memory, while each subsequent word takes 5 ns. The word size is 64 bits. The average memory access time in ns (round off to 1 decimal place) is _____.