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

Basic difference between java and c++, Both Java and C++ use same syntax an...

Both Java and C++ use same syntax and are Object Oriented, but there are several differences between Java and C++:   1.    Java does not use pointers. Pointers are inherently

State about the garbage collection, Explain garbage collection. Java us...

Explain garbage collection. Java uses garbage collection to free the memory. By cleaning those objects which is no longer reference by any of the program. Step involve in clean

Give an examples of access protection, Give an Examples of Access Protectio...

Give an Examples of Access Protection ? This is how the Car class would almost certainly be written in practice. Remember that all the fields are now declared private, and the

What is the order of function invocation in an applet? , The Applet's life ...

The Applet's life cycle functions are as follows: public void init() : Initialization function called only once by the browser. public void start() : Method called after

What are the flow control statements in java? , The flow control statement...

The flow control statements give you to conditionally execute statements, to repeatedly operate a block of statements, or to just modify the sequential flow of control.

Netbeans, how can i create an E-exam application on netbeans

how can i create an E-exam application on netbeans

Relate java with C/C++, Relate Java with C/C++ Very similar C/C++ synta...

Relate Java with C/C++ Very similar C/C++ syntax, operators, etc. Core language is simpler than C++ -- no pointers, no operator overloading, and no multiple inheritance.

Why local variable is preferred over global variable, Why Local variable is...

Why Local variable is preferred over Global variable ? In my point of view Global variable has a few advantage along with Local variables is preferred because of the subsequent

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