Operating Systems

Process vs Thread

Process Control Block (PCB)

Process States & Transitions

Context Switching

User-Level vs Kernel-Level Threads

Multithreading Models

Process Creation: fork, exec, wait

Inter-Process Communication (IPC)

Daemon Threads

Thread Pools

Concurrency vs Parallelism

Process vs Program

CPU Scheduling Criteria

FCFS Scheduling

SJF & SRTF Scheduling

Round Robin Scheduling

Priority Scheduling & Starvation

Multilevel Queue Scheduling

Preemptive vs Non-Preemptive Scheduling

CPU Scheduling in Java

Memory Hierarchy

Virtual Memory & Address Space

Paging

Segmentation

Page Faults & Demand Paging

Translation Lookaside Buffer (TLB)

Page Replacement Algorithms

Thrashing

Internal vs External Fragmentation

Contiguous Memory Allocation Strategies

Race Condition & Critical Section

Mutex vs Semaphore

Monitors & Condition Variables

Producer-Consumer Problem

Readers-Writers Problem

Dining Philosophers Problem

Deadlock: Four Necessary Conditions

Resource Allocation Graph

Deadlock Prevention

Deadlock Avoidance: Banker's Algorithm

Deadlock Detection & Recovery

Livelock & Starvation

File System Structure & Inodes

File Allocation Methods

Directory Structure

Journaling File Systems

I/O Techniques: Polling, Interrupts & DMA

Disk Scheduling Algorithms

System Calls & Kernel Mode

Memory-Mapped I/O & Files