Process Simulator

CPU scheduling algorithm (FCFS, SJF, SRTF, Priority-based Scheduling , Preemptive Priority-based Scheduling, Round Robin) and deadlock avoidance algorithm (Banker’s Algorithm) are implemented in this project.

List of Commands

The following commands are working in my project.

Command	Remarks
create-process	Create a new process.
ready-process	Transfer processes from job queue to ready queue and device queue. Also call the function bankers_algorithm() to check system is safe or not if there is any process in device queue.
show-job-queue	Show all process in job queue.
show-ready-queue	Show all process in ready queue.
show-device-queue	Show all process in device queue.
execute-process	Execute all process in ready queue, before that users have to select a scheduling algorithm to start execution.
reexecute-process	Re-execute all process in ready queue including all terminated process.
change-status	Switch state of a process to another state. There are five option to switch state of a process, user has to select an option, then also need to select a particular process. Enough frames must be available in memory to switch state of a process to ‘ready’ state. If state of a process switch to ‘waiting’ state bankers_algorithm() function will be called to check system is safe or not.
show-memory-map	Display all frames in memory.
clear	Clear the screen.
exit	Terminate the process simulator

NB: As many functions depending on the data stored by the sysConfig(), it will be called automatically at the beginning of the program.

Data Structure used

I have used the data structure, Vector and also Queue in some cases, as given in the sample project.

CPU Scheduling Algorithms

The following CPU scheduling algorithms are implemented.

• FCFS
• SJF
• SRTF
• Priority-based Scheduling
• Preemptive Priority-based Scheduling
• Round Robin

Banker’s Algorithm for Deadlock Avoidance

This algorithm is implemented in my project. After executing this algorithm –

• If the system is safe, safe sequence will be printed.
• If the system is unsafe, one process will be preempted and banker’s algorithm will be called, if the system is still unsafe, another process will be preempted and again the banker’s algorithm will be called. This process will continue until the system is in the safe state.

Memory Management

• Process will be sent to ready queue according to available frame number in memory.
• Users can view which frame is allocated to which process and which frames are empty.