Ask Question, Ask an Expert

+1-415-315-9853

info@mywordsolution.com

Ask Computer Engineering Expert

1. Describe in detail the consistency model of the distributed file system (GFS or AFS). Present the consistency model selected and how it was achieved through design. Clarity of presentation matters, so take your time to formulate your answer clearly.

2. Suppose you are provided a uniprocessor system with one gigabyte of memory and a 300 gigabyte disk. The OS on the machine has a demand paged virtual memory system with a local page replacement policy and a multi-level feedback queue (MLFQ) CPU scheduler. On the system there are two compute-intensive jobs running: Job-A and Job-B. Job-A has a working set of 50 gigabytes while Job-B has a working set of 100 megabytes. Suppose you left the system to execute for a while till it reached a steady state with both jobs running.

a. Which job will you expect to have a higher CPU scheduling priority from MLFQ scheduler?

b. Suppose you add the second CPU to system, how will this affect priorities of the jobs?

c. Suppose you switch from a local to the global page replacement policy, how does this alteration affect priorities of the jobs? Justify your answer and state any assumptions you make.

3. Consider organization of a UNIX file as represented by the inode. Suppose there are 13 direct block pointers and a singly, doubly and triply indirect pointer in each inode. Further, Suppose that system block size and the disk sector size are both 4K. If the disk block pointer is 32 bits, then:

a. Find the maximum file size supported by this system?

b. Supposing no information other than file inode is already in main memory, how many disk accesses are needed to access the byte in position 5Y3+100, where Y=1024?

4.a. Define the term “deadlock”. There are four conditions which should hold before deadlock is possible. Name them.

b. Outline the algorithm which detects whether there is a deadlock. The algorithm must be able to cope with multiple types of resources, each type having a limited number of units available.

c. When must the algorithm be invoked? The answer to this problem might depend on system characteristics like the rate of resource requests, the granularity of resources, and the expected rate of deadlock. List three possible choices and discuss the criteria you will use to choose among them.

5. Assume an instruction takes 1 nanosecond to execute (on average), a page fault takes 20 microseconds of processor time, and it takes 300 microseconds of disk time to read or prepare a single page. Assume that on average, 1/2 of the pages are modified. What is the average number of instructions between page faults which will cause the disk to be busy doing page transfers all the time?

6. List three broad design goals of the ESX memory management system, and briefly outline how the design meets those goals.

7. Consider a system implementing multilevel feedback queue scheduling. What strategy could a computer user employ to maximize amount of CPU time allocated to the user’s process?

8. Your OS has a set of queues, each of which is protected by a lock. To enqueue or dequeue an item, a thread should hold the lock associated to the queue. 
}

You require to implement an atomic transfer routine which dequeues an item from one queue and enqueues it on another. The transfer should appear to occur atomically. This is your first attempt:

void transfer(Queue *q1, Queue *q2) {
Item thing; /* the thing being transferred */
q1->lock.Acquire(); thing = q1->Dequeue(); if (thing != NULL){
q2->lock.Acquire(); q2->Enqueue(thing); q2->lock.Release();
} q1->lock.Release()

You might suppose that q1 and q2 never refer to the same queue. Also, suppose that you have a function Queue::Address which takes a queue and returns, as an unsigned integer, its address in memory.

a. Describe how using this implementation of transfer leads to deadlock; 

b. prepare a modified version of transfer which avoids deadlock and does the transfer atomically;

c. If the transfer does not require to be atomic, how may you modify your solution to achieve a higher degree of concurrency? Justify how your modification increases concurrency.

Computer Engineering, Engineering

  • Category:- Computer Engineering
  • Reference No.:- M91856

Have any Question? 


Related Questions in Computer Engineering

There are a number of other notions of edit distance

There are a number of other notions of edit distance available. For instance, we can allow, in addition to insertions and deletions, the following operations: i. Mutation, where one symbol is replaced by another symbol. ...

What should chantale dowhat are the reasonable limits on

What should Chantale do? What are the reasonable limits on loyalty to one's employer? Would it make a difference if Chantale had a position of greater authority? Would it make a difference if Chantale had scientific expe ...

Describe the function point analysis technique for deriving

Describe the Function Point Analysis technique for deriving effort and cost estimates for software projects? Describe the COCOMO technique for deriving effort and cost estimates for software projects?

R and exploring iris dataquestion what is the format to use

R and Exploring Iris Data Question: What is the format to use to Run the command to display all 6 descriptive statics of the Petal.Width variables Question Run the command to search the help pages for information on plot ...

How do you choose the appropriate active directory

How do you choose the appropriate Active Directory replication topology for your company? What kinds of problems do you want to prevent? Give examples. Please explain in approximately in two paragraphs.

Consider the cd cover in figure 5-61a specify identifiers

Consider the CD cover in Figure 5-61. A. Specify identifiers and attributes for the entities CD, ARTIST, ROLE, and SONG. B. Construct a crow's foot model showing relationships among these four entities. Name each relatio ...

Write an sql statement to create a view named finance

Write an SQL statement to create a view named Finance Employee Phone View that shows the values of EMPLOYEE. Last Name as Employee Last Name, EMPLOYEE. First Name as Employee First Name, and EMPLOYEE. Phone as Employee P ...

Consider the entrepreneur described in section 141 and

Consider the entrepreneur described in Section 14.1 (and referenced in Tables 14.1-14.3). Suppose she funds the project by borrowing $750 rather than $500. According to MM Proposition I, what is the value of the equity? ...

Using the sample data for the computer table shown in

Using the sample data for the COMPUTER table shown in Figure 7-37 and the COMPUTER_ASSIGNMENT table shown in 7-38, write INSERT statements to add this data to these tables in the WPC database. Run these INSERT statements ...

Genetic counselingexplain tay-sachs disease imagine you are

Genetic Counseling Explain Tay-Sachs disease. Imagine you are a genetic counselor working with a couple who have just had a child who is suffering from Tay-Sachs disease. Neither parent has been tested for Tay-Sachs dise ...

  • 4,153,160 Questions Asked
  • 13,132 Experts
  • 2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

A cola-dispensing machine is set to dispense 9 ounces of

A cola-dispensing machine is set to dispense 9 ounces of cola per cup, with a standard deviation of 1.0 ounce. The manuf

What is marketingbullwhat is marketing think back to your

What is Marketing? • "What is marketing"? Think back to your impressions before you started this class versus how you

Question -your client david smith runs a small it

QUESTION - Your client, David Smith runs a small IT consulting business specialising in computer software and techno

Inspection of a random sample of 22 aircraft showed that 15

Inspection of a random sample of 22 aircraft showed that 15 needed repairs to fix a wiring problem that might compromise

Effective hrmquestionhow can an effective hrm system help

Effective HRM Question How can an effective HRM system help facilitate the achievement of an organization's strate