Java Page Replacement Simulation with Clock Algorithm

Exploring Java OS Page Replacement Strategies with the Clock Algorithm

Dive into a comprehensive Java implementation delving into operating system page replacement strategies via the clock algorithm. The code, encapsulated in the OperatingSystem class, adeptly orchestrates simulations for both fixed-local and variable-global replacement policies. Through meticulous tracking of crucial metrics such as turnaround time and fault occurrences, this code provides valuable insights into optimizing memory management techniques. Whether you are a student exploring Java assignments or seeking assistance with intricate coding challenges, this resource illuminates the systematic evaluation of page replacement methods. Explore how the clock algorithm enhances efficiency and performance in handling dynamic memory scenarios, offering valuable guidance for those seeking help with their Java assignment.

Block 1: Class Declaration


public class OperatingSystem {
private final int totalFrames;
private final int quantum;
private final List processes;
public OperatingSystem(int totalFrames, int quantum, List processes) {
this.totalFrames = totalFrames;
this.quantum = quantum;
this.processes = processes;
}

The OperatingSystem class has three private fields: totalFrames (total number of frames in the system), quantum (quantum time for process execution), and processes (a list of processes).
The constructor initializes these fields based on the input parameters.

Block 2: Simulation Method


public void simulate() {
ClockAlgorithm clockFixedLocal = new ClockAlgorithm(totalFrames / processes.size());
ClockAlgorithm clockVariableGlobal = new ClockAlgorithm(totalFrames);
simulateReplacementStrategy("Clock - Fixed-Local Replacement:", true, clockFixedLocal);
resetProcesses();
simulateReplacementStrategy("Clock - Variable-Global Replacement:", false, clockVariableGlobal);
}

The simulation method sets up two instances of ClockAlgorithm (page replacement algorithm) with different configurations.
It then calls simulateReplacementStrategy for both algorithms, printing, and resetting processes between the simulations.

Block 3: Replacement Strategy Simulation


private void simulateReplacementStrategy(String header, boolean isFixed, ClockAlgorithm clock) {
int time = 0;
while (true) {
boolean allProcessesCompleted = true;
for (Process process : processes) {
if (!process.getPageRequests().isEmpty()) {
allProcessesCompleted = false;
time = simulateProcess(isFixed, clock, process, time);
}
}
if (allProcessesCompleted) break;
}
writeResultsToFile(header);
printResults(header, time);
}

The simulateReplacementStrategy method simulates the page replacement strategy for all processes until they are completed.
It calls simulateProcess for each process to execute page requests and updates the simulation time.
Results are written to a file and printed to the console after the simulation.

Block 4: Process Simulation


private int simulateProcess(boolean isFixed, ClockAlgorithm clock, Process process, int startTime) {
// ...
}

The simulate process method simulates the page requests of a specific process using the given page replacement algorithm.
It iterates through the process's page requests, handles page faults, and updates process statistics (faults, fault times).
The method returns the updated simulation time.

Block 5: Process Reset


private void resetProcesses() {
for (Process process : processes) {
process.reset();
}
}

The resetProcesses method resets all processes by calling their reset method.

Block 6: Results Printing


private void printResults(String header, int time) {
// ...
}

The printResults method prints the simulation results to the console, including process ID, name, turnaround time, faults, and fault times.

Block 7: Results Writing to File


private void writeResultsToFile(String header) {
// ...
}

The writeResultsToFile method writes the simulation results to the "output.txt" file, including process information, turnaround time, faults, and fault times.

Conclusion

In conclusion, this Java implementation illuminates the intricacies of operating system page replacement strategies, offering a valuable resource for both learners and those seeking assistance with Java assignments. By navigating the simulations for fixed-local and variable-global replacement policies, this code provides insights into crucial metrics and optimization techniques for memory management. Whether you are a student exploring the nuances of Java programming or someone grappling with the complexities of coding challenges, this resource serves as a guide to understanding and implementing effective page replacement methods. Embrace the knowledge embedded in this code, and empower yourself to tackle diverse scenarios in dynamic memory environments.

Simulating Page Replacement Strategies with Clock Algorithm in Java