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

Explain drawing rectangles in java, Explain Drawing Rectangles in java ? ...

Explain Drawing Rectangles in java ? Drawing rectangles is easy. Begin with a Graphics object g and call its drawRect() method: public void drawRect(int x, int y, int width, i

Want a page to store emails when click as save, Want a page to store emails...

Want a page to store emails when click as save, then pass along to another page with the emails in the URL Project Description: I have a page that populates with listing; the

What is jar archives, What is JAR archives? JAR archives are ZIP archiv...

What is JAR archives? JAR archives are ZIP archives along with a different extension. They contain a hierarchy of files and directories. In spirit a JAR file can take the place

How we declaring arrays in java language, How we Declaring Arrays in java l...

How we Declaring Arrays in java language? Like all other variables in Java, an array must have a exact type such as byte, int, String or double. Just variables of the appropria

Cross platform stock market game, Cross platform stock market game Proje...

Cross platform stock market game Project Description: I want someone to develop a simple stock market game. This will mainly be a facebook and android app, face book being mo

What is scope of variable in java, What is Scope of Variable ? Space in...

What is Scope of Variable ? Space in that a variable is effective is called as the scope of a variable. In other words we can say area where that variable is available for the

Relational mapping integration module, What are object/relational mapping i...

What are object/relational mapping integration module? Ans) Spring also supports for using of an object/relational mapping (ORM) tool over straight JDBC by giving the ORM module

Control graphical user interface elements, Introduction In this assign...

Introduction In this assignment you will use Processing to create some geometric objects and graphical user interface (GUI) elements that Processing itself lacks. Processing h

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