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

What type of operations takes place inside microprocessors, What type of op...

What type of operations takes place inside Microprocessors Building Blocks? Enlist them along with brief description. Bus Interface Unit: The bus interface unit is the part o

What is the difference between internet and intranet, What is the differenc...

What is the difference between Internet and Intranet ? Intranet and internet are 2 domains which are extremely a like but frequent segregated in order to manage security. Inter

Explain how several ways businesses monitor their employees, Explain how se...

Explain how several ways businesses monitor their employees? Systems are available in which monitor or most every key stroke which an employee forms on computer. Systems are av

Combo box and Check box help, Sal?s Pizza wants to install a system to reco...

Sal?s Pizza wants to install a system to record orders for pizza and Buffalo chicken wings. When regular customers call Sal?s Pizza on the phone, they are asked their phone number.

Program that instantiates a number of actors and writers, Talent agencies l...

Talent agencies like ICM, CAA and Paradigm represent writers, directors and actors (among other talent).  These agencies take in hundreds of millions of dollars a year collecting 1

Java, 1. Which of the following are not valid Java identifiers, and why? (...

1. Which of the following are not valid Java identifiers, and why? (a) wolVes (b) United(there is only one) (c) 87 (d) 5 3 (e) Real ale (f) isFound?by 2. A class Television

How trojan horses or worms affect a computer system, How Trojan Horses or W...

How Trojan Horses or Worms affect a computer system? What guidelines should be adopted to troubleshoot along with malicious software? Trojan horses are stand-alone programs. Th

We want the best java programmer, We want the best java programmer availabl...

We want the best java programmer available. Project Description: Java | Portlets| JSF Liferay (not essential but is preferable) Big Data and User online tools. Multilin

Computer application and program, Computer application and program. Proj...

Computer application and program. Project Description: I require a project done. It is a computer desktop application program. It is not very hard. Skills required: Any

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