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

What is meant by universal access of internet services, What is meant by un...

What is meant by universal access of internet services ? the meaning of Universal access of internet services means same functionality to everyone.

Program to create shipping company model, This assignment models a simplifi...

This assignment models a simplified delivery company. It is composed of the following departments:  receiving which contains a list of packages to be delivered, shipping which ship

Vehicle loan application - weblogic administrator, Vehicle Loan Application...

Vehicle Loan Application: Type                                         Web-based Application Role                                          Weblogic administrator + develop

What is alternate text, What is Alternate Text ? The APPLET element ca...

What is Alternate Text ? The APPLET element can have an ALT attribute. An ALT attribute is used through a browser which understands the APPLET tag but for some purpose cannot

Assignments, Define a function that will take a box type of object as argum...

Define a function that will take a box type of object as argument and return a box object whose dimension is 10 times more than the object

Luminous jewels, Luminous Jewels - The Polishing Game Byteland county is v...

Luminous Jewels - The Polishing Game Byteland county is very famous for luminous jewels. Luminous jewels are used in making beautiful necklaces. A necklace consists of various lum

Why the number of temporary workers is on the rise, Why the number of tempo...

Why the number of temporary workers is on the rise? Discuss main reasons? Temporary workers: Temporary workers are those workers that a company can hire to perform a certain ta

Unix-like CLI in Java (simple), The assignment is implementing a CLI in Jav...

The assignment is implementing a CLI in Java with several usable commands, using Threads.

I want java web developer, Project Description: A web developer is requi...

Project Description: A web developer is required to finish a webcam site with basic account management and voting functionality. The website can make use of a third party fla

Rest client, Modify both of the above clients (to write separate clients) t...

Modify both of the above clients (to write separate clients) to extract the exchange rate from a live web service that performs currency conversion. You can choose a Java or a .NET

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