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 identifiers in java, Explain Identifiers in Java ? Identifiers ...

Explain Identifiers in Java ? Identifiers are the names of variables, classes, methods, packages and interfaces. Unlike literals they are not the things themselves, only ways o

Basic java, Why is Java platform independent / architecturally neutral / po...

Why is Java platform independent / architecturally neutral / portable?

What is difference between design and system architecture, What is differen...

What is difference between Design and System Architecture? System architecture is the conceptual design which defines the structure and/or behavior of a system. Whereas designs

Banknote ocr register anti fraud, Project Description: Introduction: ...

Project Description: Introduction: SID C.A. (integradores) is a software company in Venezuela 15 years ago, and we are exploring the possibility of making mobile developments

Java server faces - eagro portal project, eAgro Portal Project: Techno...

eAgro Portal Project: Technology Used: Java Server Faces, JSR 168 Specification, Websphere Portal Server5.0, DB2 database And Rational Application Developer, Jasper Report Too

Decsion tree, implementation of DT in netbeans

implementation of DT in netbeans

Area under curve, write a program to find the area under thecurve y=f(x)bet...

write a program to find the area under thecurve y=f(x)between x=a and x=b, integrate y=f(x) between the limits of a and b. the area under a curve between two points can be found by

Bluej program, program to find the frequency of a digit in a number

program to find the frequency of a digit in a number

Kik messenger program, Kik Messenger is a plan mobile messenger like Skype....

Kik Messenger is a plan mobile messenger like Skype. It's available on each major smart phone for Android and Iphone. Here is the entire process: Could be able to add multipl

What can you do with an exception once you''ve caught it, What can you do w...

What can you do with an exception once you've caught it? 1. Fix the difficulty and try again. 2. Do anything else instead. 3. Exit the application along with System.exit() 4

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