In the following program, the main thread creates four peer threads and passes a pointer to the loop variable to each one. Each peer thread prints a message containing the loop variable. 1 #include 2 #include 3 4 void *foo (void *arg) { 5 int *myid = (int *) arg; 6 printf ("Hello from thread %d\n", *myid); 7 return NULL; 8} 9 10 int main() { 11 12 13 14 15 16 17 18 19 20 21 } pthread_t tid [4]; int i; for(i=0; i<4; i++) pthread_create(&tid[i], NULL, foo, &i); for(i=0; i<4; i++) pthread_join(tid[i], NULL); return 0; We might expect that the program will print all the four values of i, but when the program is executed, we see the following incorrect result containing repetitions: Hello from thread 1 Hello from thread 3 Hello from thread 3 Hello from thread 3 What causes this behavior? Explain your answer. ) [Continuation of Question 2b above] Rectify only the main() function such that the concurrent peer threads print unique values, i.e., the first thread prints 0, the second thread prints 1, the third thread prints 2 and the final thread prints 3. We don't expect the threads will print "in order" (we expect that they just print the correct value per thread). Explain your answer.

In the following program, the main thread creates four peer threads and passes a pointer to the loop variable to each one. Each peer thread prints a message containing the loop variable. 1 #include 2 #include 3 4 void foo (void arg) { 5 int myid = (int ) arg; 6 printf ("Hello from thread %d\n", *myid); 7 return NULL; 8} 9 10 int main() { 11 12 13 14 15 16 17 18 19 20 21 } pthread_t tid [4]; int i; for(i=0; i<4; i++) pthread_create(&tid[i], NULL, foo, &i); for(i=0; i<4; i++) pthread_join(tid[i], NULL); return 0; We might expect that the program will print all the four values of i, but when the program is executed, we see the following incorrect result containing repetitions: Hello from thread 1 Hello from thread 3 Hello from thread 3 Hello from thread 3 What causes this behavior? Explain your answer. ) [Continuation of Question 2b above] Rectify only the main() function such that the concurrent peer threads print unique values, i.e., the first thread prints 0, the second thread prints 1, the third thread prints 2 and the final thread prints 3. We don't expect the threads will print "in order" (we expect that they just print the correct value per thread). Explain your answer.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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-0-0- thread (const thread&) = delete; thread& operator=(const thread&) = delete; void swap(thread& _Other) noexcept { _STD swap(_Thr, _Other._Thr); } _NODISCARD bool joinable() const noexcept { return _Thr._Id != 0; x void join() { if (!joinable()) { _Throw_Cpp_error(_ } if (_Thr._Id == _Thrd_ _Throw_Cpp_error(_ } if (_Thrd_join(_Thr, n Exception Thrown Exception thrown: read access violation. this was nullptr. _Thr = {}; Copy Details | Start Live Share session... ✔ Exception Settings ✔ Break when this exception type is thrown Except when thrown from: Reservation System.exe Open Exception Settings Edit Conditions _Throw_Cpp_error(_Code: _NO_SUCH_PROCESS); ох E..
Errors produced when calling 3. Find the maximum element from the BST or4. Find the minimum element from the BST before adding elements so the program should output 0(0) instead of an error "Exception in thread "main" java.lang.NullPointerException: Cannot read field "right" because "<local1>" is null at BST.findMax(BST.java:109) at BST.main(BST.java:194)" "Exception in thread "main" java.lang.NullPointerException: Cannot read field "left" because "<local1>" is null at BST.findMin(BST.java:118) at BST.main(BST.java:197)"
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Exercise 1: Write a thread class TabPrinter that prints the elements of an array of integers (in one line) every 2 seconds 5 times. Use the way of extending the class thread. Write the main method which creates and starts three threads Printer which will print different arrays of integers. After that it prints "Main won’t wait. Main exits". Modify the above thread program so that you implement the interface Runnable. Make the main thread waiting till all other threads finish execution. ____________________________________________________________________________________________ Exercise 2: Write a thread class TextThread that prints a text every 1 second 10 times. Read the following main class. Try to guess what will be its output. class Test { public static void main(String s[]) throws Exception { TextThread x = new TextThread ("I am thread x"); TextThread y= new TextThread ("I am thread y"); System.out.println("I am Main thread"); } } Write it and execute it. Is the…
Lab Activities: Exercise 1: 1) Write a thread class TabPrinter that prints the elements of an array of integers (in one line) every 2 seconds 5 times. Use the way of extending the class thread. Write the main method which creates and starts three threads Printer which will print different arrays of integers. After that it prints "Main won't wait. Main exits". 2) Modify the above thread program so that you implement the interface Runnable. Make the main thread waiting till all other threads finish execution.
Currently, work is being performed by a thread with priority 30. What would be (areassigned )'s priority if it used all of its allocated time? If b is accurate, then I/O is blocked.
Question No:1 Write a Java program that creates three threads namely SumCalculator, AverageCalculator and LargestCalculator The first thread displays the sum of three courses marks whereas the second thread displays the average of the courses' marks. The last thread displays the highest marks in the courses. The courses' marks will be passed to the thread by using the thread constructor Also write the client program that runs all three threads
Parallel version 1 (Name this file as Q1_PLV1.java): o Repeat the sequential version using two threads along with the main thread. o Each thread creates a list of 25,000 students with randomly generated GPAs, randomly generated Ages, and sequential IDs. o Each of the two threads then calculates the average GPA and AGE (after creating the lists). o The two threads work in parallel. o The main thread waits for the two threads to finish and then calculates and prints the final average GPA and AGE from what is reported by the individual threads. • Parallel version 2 (Name this file as Q1_PLV2.java): o Repeat the Parallel version1 task using five threads (each is working on 10000 students) along with the main thread. To measure the time your computer takes to complete a certain task: • Read and store the current time (t1) before you start the task (e.g., before creating the lists), • After the task (e.g., after calculating the average), read and store the current time (t2). • The…
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Needed to be done in 20 minutes