Understanding the Core of Computer Systems

Kernel Architecture

The kernel is the core of an operating system. It’s a privileged mode program that manages hardware resources directly. Key responsibilities include managing CPU time, memory allocation, and device drivers.

There are various kernel architectures: Monolithic kernels (like Linux) integrate all OS services into a single address space, offering speed but potential instability. Microkernels minimize the code running in kernel mode, increasing robustness.

Process Management

A process is an instance of a program being executed. The OS manages processes through techniques like context switching – rapidly switching between processes to give the illusion of simultaneous execution.

Processes communicate using mechanisms like pipes and shared memory, enabling inter-process communication (IPC). Process scheduling algorithms determine which process gets CPU time.

CPU Time = Scheduling Algorithm * Priority

Memory Management

Efficient memory management is critical for performance. The OS employs techniques like virtual memory to allow programs to use more memory than physically available, swapping data between RAM and secondary storage.

Page tables map virtual addresses (used by processes) to physical addresses in RAM. Memory protection prevents one process from corrupting the memory of another.

Virtual Address = Physical Address + Page Offset

File Systems

A file system organizes data on storage devices (hard drives, SSDs) into files and directories. Common file systems include NTFS (Windows), ext4 (Linux), and APFS (macOS).

The OS provides an interface for accessing files through system calls. These calls allow programs to read, write, create, and delete files.

Frequently asked questions

Try it live

Everything above runs in your browser — open SPH Fluid and change the parameters while it is running. Nothing is installed, nothing is uploaded, the whole model lives in one tab.