Caching "One of the Keys to Happiness Is a Bad

question 6

Essay

Caching. "One of the keys to happiness is a bad memory." -Rita Mae Brown Consider the following piece of code:
int x = 0, y = 0; // The compiler puts x in r1 and y in r2. int i; // The compiler put i in r3.
int A[4096]; // A is in memory at address 0x10000
...
for (i=0;i<1024;i++) { x += A[i];
}
for (i=0;i<1024;i++) { y += A[i+2048];
}
(a) Assume that the system has a 8192-byte, direct-mapped data cache with 16-byte blocks. Assuming that the cache starts out empty, what is the series of data cache hits and misses for this snippet of code. Assume that ints are 32-bits.
(b) Assume that an iteration of a loop in which the load hits takes 10 cycles but that an iteration of a loop in which the load misses takes 100 cycles. What is the execution time of this snippet with the aforementioned cache?
(c) Repeat part A except assume that the cache is 2-way set associative with an LRU replacement policy and 16-byte sets (8-byte blocks).
(d) Repeat part B using the cache described in part C. Is the direct-mapped or the set-associative cache better?

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Definitions:

Aymara Indians

The Aymara Indians are an indigenous people who live in the Andes mountains region, mainly in present-day Bolivia, Peru, and Chile, known for their rich cultural heritage and traditional ways of life.

Gender

Refers to the social, cultural, and behavioral attributes, expectations, and norms associated with being male or female.

Teknonymy

A naming practice where a parent is referred to by the name of their child, commonly found in various cultures around the world.