Operating Systems Questions (Please help if you can)

1. What is the distinction between spatial locality and temporal locality?

2. Consider a memory system with the following parameters:

Tc = 100ns Cc = 0.01cents/bit

Tm = 1200ns Cm = 0.001cents/bit

Tc and Cc are the access time and cost for cache memory, respectively. Tm and Cm are the

access time and cost for main memory, respectively.

(a) What is the cost of 1MByte of main memory?

(b) What is the cost of 1MByte of main memory built using cache memory technology?

(c) If the effective access time is 10% greater than the cache access time, what is the hit

ratio H?

3. In a multiprogramming and time-sharing environment, several users share the system

simultaneously. This situation can result in various security problems.

(a) Name two such problems.

(b) Can we ensure the same degree of security in a time-shared machine as a dedicated

machine? Explain your answer.

4. What is the distinction between blocking and nonblocking with respect to messages.