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

Application to control robot arm , I send you these files in order to make ...

I send you these files in order to make clear image about my task that I want you to design for me an application for PC that used to control robot arm via micro controller PIC18.

Difference between hashmap and hash table, Difference between HashMap and H...

Difference between HashMap and Hash table HashMap: It allow us to have null values and also one null key It is Unsynchronized. Iterator in HashMap is Fail-Safe.

How many ways are there to call a function in a program, How many ways are ...

How many ways are there to call a function in a program? Explain with example? Two Ways of Calling Functions: Functions do not run automatically. While the page loads, every

What is my personal agent, What is "My Personal Agent"? My personal age...

What is "My Personal Agent"? My personal agent is a computer programme which work automatically and have voice interface.

MATLAB, Requested figure handle in use by another object, how do i fix this...

Requested figure handle in use by another object, how do i fix this?

Create an android application., We need to create an Android application. T...

We need to create an Android application. The application is about registering courses in a university, viewing grades, available courses and evaluating faculty members. Advisor

What does it mean that a method or field is static, What does it mean that ...

What does it mean that a method or field is "static"? Static variables and methods are instantiated only once per class. In other words they are class variables, not example va

Describe the four levels of access protection, Describe the Four Levels of ...

Describe the Four Levels of Access Protection ? Any two various Java objects have one of four relations to each other. The four relations are: • The objects are in the simila

For statement in javascript, A for loop repeats until a specified condition...

A for loop repeats until a specified condition evaluates to false. For for loop the JavaScript is similar to the Java and C for loops. A for statement looks as:  for ([initial-

Write a program to add integer value, Write a program to add integer value?...

Write a program to add integer value? class AddInts { public static void main (String args[]) { int i = 1; int j = 2; System.out.println("i is " + i); System.out.println("

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