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.
1
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

Distributed ticket reservation system, In this programming assignment, you ...

In this programming assignment, you are going to implement the simple distributed ticket reservation system (DTRS) from Assignment 1 in CORBA using Java IDL. In addition to the thr

Animal trim java, Create an application for an animal-fur trimming service....

Create an application for an animal-fur trimming service. The business is open 15 weeks of the year, from April through July. The fee for a small animal (under 6 pounds) is $100, a

La food, The fancy new French restaurant La Food is very popular for its au...

The fancy new French restaurant La Food is very popular for its authentic cuisine and high prices. This restaurant does not take reservations. To help improve the efficiency of the

String, in java string is a

in java string is a

What is an abstract class, What is an abstract class? Abstract class mu...

What is an abstract class? Abstract class must be extended/subclassed (to be useful). It serves as a template. A class that is abstract may not be instantiated (ie. you may not

Game, any example of games that is created by java ?

any example of games that is created by java ?

Java coding required, Java coding required Project Description: Need ...

Java coding required Project Description: Need to develop a website. Require Java coders urgently. Skills required are Graphic Design, HTML, PHP, Java, Website Design

Require assistance in java / grails support, require assistance in Java / G...

require assistance in Java / Grails support We have a project which requires continuous maintenance / support and occasional feature development. Its running on Java 1.7 / Grail

Why class can''t extend more than one class, Why is an Interface be able to...

Why is an Interface be able to extend more than one Interface but a Class can't extend more than one Class? Basically Java doesn't permit multiple inheritances, so a Class is r

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