Concurrent Programming, JAVA Programming

Assignment Help:
Problem 1
A savings account object holds a non-negative balance, and provides deposit(k )
and withdraw(k ) methods, where deposit(k ) adds k to the balance, and
withdraw(k ) subtracts k, if the balance is at least k, and otherwise blocks until
the balance becomes k or greater. getbalance() gives the current balance.
1. Implement this savings account using locks and conditions (use
java.util.concurrent.locks.ReentrantLock). Test by using the 3
functions.
2. Now suppose there are two kinds of withdrawals: ordinary and preferred.
Devise an implementation that ensures that no ordinary withdrawal occurs
if there is a preferred withdrawal waiting to occur.

Problem 2
Consider the following conditions: An enqueuer waiting on a full-queue or
a dequeuer waiting on an empty queue sleep indefinitely, unless woken up by
another thread. A thread must send a signal ONLY when it adds an element
to an empty queue or removes an element from a full-queue.
1. Implement a bounded partial queue using a signaling mechanism that
signals to all waiting dequeuers.
2. Implement the bounded partial queue by using a signaling mechanism
(your own scheme) that signals to only one waiting dequeuer or enqueuer,
and ensure that the lost-wake-up problem does not happen.


Problem 3
We have n threads, each of which executes method foo() followed by bar().
We want to add synchronization to ensure that no thread starts executing bar()
until all threads have finished executing foo(). To achieve this, we will insert
some barrier code between the two methods. Implement the following two
schemes for barrier code:
• Use a shared counter protected by test-and-test-and-set lock. Each thread
locks the counter, increments it, releases the lock, and repeatedly reads
the counter until it reaches n.
• Use an n-element Boolean array A. Initially all entries are 0. When thread
0 executes its barrier, it sets b[0] to 1, and repeatedly reads b[n - 1]
until it becomes 1. Every other thread i, repeatedly reads b[i - 1] until
it becomes 1, then it sets b[i] to 1, and repeatedly reads b[n - 1] until
it becomes 1.
Implement both these schemes in Java. Each of the methods foo() and
bar() just sleeps for 20 milliseconds. Test the two schemes for n = 16. Run
each scheme at least ten times, measure the total runtime in each test run,
discard the highest and lowest values, take the average, and use it to compare
the two schemes. Which performs better? Can you explain the reason? You
can run the experiments on ecen5033.colorado.edu. Submit the code as well as
experimental results.

Related Discussions:- Concurrent Programming

Difference between while statement and a do while statement, What is the di...

What is the difference between a while statement and a do while statement? A while statement checks at the starting of a loop to see whether the next loop iteration should occu

How we use a car object in a different class, How we Use a Car object in a ...

How we Use a Car object in a different class ? class Car { String licensePlate; // e.g. "New York 543 A23" double speed; // in kilometers per hour double maxSpeed;

Program for write a class with the header, PART1: Write a class with the...

PART1: Write a class with the header public class OrderedPair > implements Comparable > instance variables private Key x private Key y constructor publicOrd

Sum of six digits, How do I write a java program that enters a six digit nu...

How do I write a java program that enters a six digit number and takes the sum of the six digits?

Please answer this, Assignment Help >> JAVA Programming Learning Outcomes:...

Assignment Help >> JAVA Programming Learning Outcomes: 1. Use different program control statements in a programming language 2. Demonstrate the use of arrays with a programming

Explain testing for equality with equals, Explain Testing for Equality with...

Explain Testing for Equality with equals? That's not what you expected. To contrast strings or any other kind of object you required to use the equals(Object o) techniques from

Student, need help in assignment

need help in assignment

Program using a data structure to represent a set, * Using a data structure...

* Using a data structure to represent a set * Writing and using a checked exception * Extending the Exception class What should you upload via Blackboard? The files,

IRWS AND CPP, There is this solution for cpp assignment code EM132495039, i...

There is this solution for cpp assignment code EM132495039, i need solution of this and another assignment as well kindly guide me

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd