Reference no: EM131317657

Computer Science Assignment

Answer the questions clearly, explain your answer, and show your work. Answers, even if right but without an explanation, will get no credit. The explanations need to be brief, but complete, logical, and to the point. Do not quote anybody else, use your own words. Answer in the space provided or add lines if really needed. Each question is worth 10 points!

Q1: In terms of performance gains, what role does an I/O controller located inside the peripheral device perform? (50 to 100 words should be sufficient to answer this question)

Q2: Consider the steps required to write a block of data from a disk to memory. Outline the major sequence of I/O events that must occur to make this possible. (There are three major steps)

Q3: What is the capacity of a hard drive (in GB) consisting of 120,000 tracks, 4,000 sectors, and 4 surfaces? Assume each block has 512 bytes.

Q4: Explain what is meant by wear-leveling in Flash drives?

Q5: There are two levels of scheduling. One level of scheduling determines which jobs will be admitted to the system and in what order. What does the other level of scheduling do?

Q6: Why is it so important that access to system services by application program be controlled through APIs?

Q7: How many 512 byte blocks are required to store a 1.6MB file?

Q8: Describe the Bitmap method for maintaining free space on a disk.

Q9: In servicing read and write requests for a disk, how does First-come, first-served (FCFS) scheduling work? And, why is FCFS inefficient?

Q10: In a preemptive system, what is a 'time-out'?