Operating Systems Process Management

What distinguishes a program from a process?

What state is a process in after being created but before being executed?

During which process state is the CPU actively executing the process's instructions?

Which state represents a process that is loaded into memory but not currently executing?

What happens to a process in the waiting state?

What best describes the terminated state of a process?

In which scenario would a process enter the waiting state?

Which of the following correctly lists the states a process can transition through?

What is the first state a process enters after being created?

Which state does a process enter when it requires I/O operations?

What happens to a process when its CPU time slice expires?

What information is NOT found in the Process Control Block (PCB)?

In what situation does a process transition from the Running state to the Ready state?

What does the program counter in the PCB indicate?

What state does a process return to after completing an I/O operation?

What is one function of the Process Control Block (PCB)?

Process Definition

A process is a program in execution.
It's more than just code, it includes the program counter, CPU registers, memory, and resources allocated by the operating system.
Program: A passive entity, stored on disk, waiting to be executed.
Process: An active entity, an executing program with associated resources.
Example: A Microsoft Word file is a program, when opened, it's a process.

Process States

New: Process being created (e.g., opening a PDF document)
Ready: Loaded in memory, waiting for CPU time (e.g., PDF reader, after being loaded)
Running: Being executed by the CPU (e.g., when the scheduler assigns CPU time to the PDF reader)
Waiting: Waiting for an event to complete (e.g., I/O operation like printing a PDF)
Terminated: Finished executing, removed from memory (e.g., closing the PDF reader)

Process State Transitions

New → Ready: When created, after loading into memory
Ready → Running: When the scheduler assigns CPU time
Running → Waiting: When needing an I/O operation
Waiting → Ready: When the I/O operation completes
Running → Ready: When the CPU time slice expires
Running → Terminated: When execution finishes

Process Control Block (PCB)

Data structure kept by the operating system about a process.
Includes information such as:
- Process State (new, ready, running, waiting, terminated)
- Program Counter (address of next instruction)
- CPU Registers (current values)
- Memory Management Information (memory allocated)
- I/O Status (open files, devices being used)
Example: When opening a web browser, the OS creates a PCB to track the state of the browser process (running, waiting for network data, etc.).

Explore the essential concepts of processes in operating systems, including definitions, states, and transitions. Understand the differences between programs and processes and how they interact with system resources. This quiz will test your knowledge of process states and their transitions.