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

Prepare a computer graded test, Please check out the given instruction that...

Please check out the given instruction that I received to do the assessment. I can provide you that link to go on and submit the answers. To assess your coding skills, we would

What are the core classes of the struts framework, Struts is a set of coope...

Struts is a set of cooperating classes, servlets, and JSP tags that make up a reusable MVC 2 design. ? JavaBeans components for managing application state and behavior. ? Eve

Explain continue statement with example, Explain continue statement with ex...

Explain continue statement with example? It is sometimes essential to exit from the middle of a loop. Sometimes you'll need to begin over at the top of the loop. Sometimes you'

Write a program using local variable, Write a program using local variable ...

Write a program using local variable Public void someMethod( ) { int x; //local variable System.out.println(x); // compile time error } - Constructor - Doesn't

Prepare a java program, Using Java, write the class Time which consists of ...

Using Java, write the class Time which consists of the following: (a) three private integer data members (hours, minutes and seconds). (b) a constructor to initialise the dat

Describe what is bytecode, Describe what is bytecode? It is an inst...

Describe what is bytecode? It is an instruction set. It extends with class. 'javac' compiler translates the .java file into .class. JVM interprets bytecode.

Prepare a java program to read .gpx files, Prepare a Java program to read ....

Prepare a Java program to read .GPX files Project Description: Prepare a Java program (GPX_Tracks_to_Text.Java) for Windows to: - Read every .GPX file in a provide drive a

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