Question

1. What is an instruction trace?

2) What common events lead to the creation of a process?

3) What does it mean to preempt a process?

4) What is the kernel of an OS?

5) What is swapping and what is its purpose?

6) For what types of entities does the OS maintain tables of information for management purposes?

7) What are the steps performed by an OS to create a new process?

Answer 1

1. Instruction Trace:

• A sequence of instructions that are executed by an individual process is called Instruction trace.

2. Common events that lead to the creation of a process:

• Created by OS to provide any service
• Interactive login
• Spawned by existing process
• New batch job

3. Preempting a process:

• To maximise the number of processes in the system, we swap a process from the ready state to the ready suspend state to take a resource away from a process.
  • It means giving its memory to another process.

4. Kernel of an OS:

• The kernel is a portion of the operating system that includes the most used portion of software.
• The kernel will be maintained in main memory.
• It runs in a privileged mode and responds to calls from processes and interrupts.

5. Swapping:

• Moving a process from ready state to ready suspend state is called Swapping.
• The purpose is to make the resources and processor available for new processes.

6. Types of entities for which the OS maintain tables of information for management purposes:

• Memory Tables: It will keeps track of read and virtual memory.
• I/O Tables: This table will be used by OS to manage I/O devices and channels of the computer system.
• Process Tables: This table will be used to manage processes.

7. Steps to create a new process:

• Assigning a unique PID (Process Identifier) to the new process.
• Allocating the space for the new process
• Initializing the PCB (Process Control Block)
• Setting the appropriate linkages
• Creating or expanding the other data structures