Why are Operating Systems Needed?
I turn computer science into stories, and narration, my goal and intention isn't to teach the how. It is to help people see why the Algorithms, Data Structures, and Flows exist through visualisation by connecting the systems.
The Invisible teacher that tells your computer how to think
From our last seven blogs,
We’ve seen how Computer Architecture works.
Summary:
The Logical Address of the Program Counter arrives at the Program Counter Register,
flows to the Memory Address Register (MAR) through internal links,
and via the Address Bus, it flows to the Translation Lookaside Buffer (TLB) and the Instruction Bits gets fetched from Memory Unit. —> This is the Fetch Phase
Then the Instruction bits are decoded by the Control Unit,
and we obtain four components of the Instruction format (opcode, operand, address, and destination). —> this is the Decode Phase,
operand gets fetched from the Memory Unit - Fetch(operand) Phase.
and Data flows via the Data Bus and reaches the Memory Data Register(MDR) and gets executed by the Arithmetic Logic Unit with the opcode signal commanded by the Control Unit - Execute Phase.
This is called the Instruction Cycle, the fundamental process by which a computer executes instructions.
But why do we even need an Operating System?
Let me ask a simple question:
How do we humans handle things in our lives?
We approach or get approached by different situations, environments, people, and emotions.
And we respond to them practically or emotionally based on
our past experiences.
practically - thinking of solutions based on reasoning or logic.
emotionally - based on the person, situation, and context.
Now, think about our poor machine (Computer Architecture), it’s not even a social animal like us, but even it gets approached by Us(humans) through Input/output devices(Like Mouse, Keyboard, and sensors).
And guess what?
It is also processing things just not like us.
It has its own way —> The Instruction Cycle.
It doesn’t have various ways like us to process, but still it is processing and giving us various reactions(output) - print, display, speaker, communication via networks.
So what taught us how to process?
For humans, the reasons are:
One may be Genetics and our evolution.
Second, our Society taught us how to behave.
Third, our parents, teachers, and friends are guiding us personally
Fourth, our experiences.
So, who is teaching or telling how to process our Instructions to Computer Architecture?
It is the Operating System guys!!!
it decides which program’s instructions are loaded, when they are scheduled, and how system resources are allocated (which turns out to be Instruction Format Components)to execute, and when specific processes should be executed by Computer Architecture.
So, now we know why Operating Systems are needed!
In the next few blogs,
- We will explore how the OS handles processes, their process states, and how they communicate with the Architecture.
Hint: Remember the Address of the Program Counter arriving at the PC register from our summary. We will soon uncover how its address reaches the PC Register and how that connects to process states.
