Handwritten notes · Part 7
Operating System Handwritten Notes for Placements (Free PDF)
By Gaurav SharmaPublished
26 pages of handwritten-style OS notes for placements and interviews: processes, threads, CPU scheduling with Gantt charts, mutex vs semaphore, deadlock and Banker's algorithm, paging, virtual memory, page replacement and disk scheduling, with solved numericals, in English with Hinglish.
- Pages
- 26
- Format
- A4 PDF
- Language
- English + Hinglish
- Price
- Free by email
What's inside
24 topics, one page each
- 01What an OS does, user vs kernel mode, system calls
- 02Types of OS, monolithic vs microkernel, booting
- 03Process, PCB and process memory layout
- 04Process states, context switch, schedulers
- 05Process vs thread, concurrency vs parallelism
- 06fork(), zombie and orphan processes, IPC
- 07CPU scheduling terms and formulas
- 08FCFS and SJF with Gantt charts
- 09Round Robin, priority, SRTF and aging
- 10Race condition, critical section, Peterson's solution
- 11Mutex vs semaphore
- 12Producer-consumer, readers-writers, dining philosophers
- 13Deadlock and the four Coffman conditions
- 14Deadlock prevention, avoidance and Banker's algorithm
- 15Memory allocation and fragmentation
- 16Paging, TLB and address translation
- 17Segmentation and multi-level page tables
- 18Virtual memory, demand paging and page faults
- 19Page replacement: FIFO, LRU, Optimal, Belady's anomaly
- 20Thrashing and the working set
- 21File allocation, inodes, hard vs soft links
- 22Disk scheduling: FCFS, SSTF, SCAN, LOOK, C-SCAN
- 23Numericals and output questions
- 24Last-minute revision cheat sheet
Operating Systems is the theory subject that shows up in almost every placement interview, and the questions are surprisingly predictable: process vs thread, mutex vs semaphore, the four deadlock conditions, paging, and one scheduling or page-replacement numerical. These notes cover all of it, one topic per page, with every numerical solved.
What makes these Operating System notes different?
- Numericals solved properly. FCFS, SJF and Round Robin on the same four processes, with Gantt charts and full tables, so you can see how the averages change.
- Diagrams for the hard parts. Process states, threads in a process, address translation, the deadlock cycle and the thrashing curve, all drawn by hand.
- The comparisons interviewers ask. Process vs thread, mutex vs semaphore, paging vs segmentation, zombie vs orphan, deadlock vs starvation.
- Hinglish where it helps. Every hard concept gets a short Hinglish explanation next to the English definition.
How should you use these Operating System notes?
Solve each numerical on paper before you read the answer, then check yourself with the questions near the end. The last page is a one-page revision sheet for the night before the interview.
This is Part 7 of the series. Pair it with the SQL and DBMS handwritten notes for the other core CS subject in placement interviews.
FAQ
Questions about these notes
Are these OS notes really free?
Yes. The full 26-page PDF is free; email me to request the complete PDF. Share it with friends preparing for placements.
Do these notes include solved numericals?
Yes. FCFS, SJF and Round Robin scheduling are solved with Gantt charts and full TAT/WT tables, plus Banker's algorithm, paging address translation, effective access time, page replacement and disk scheduling, all worked step by step.
Is this enough for OS questions in placement interviews?
It covers the topics that come up most: process vs thread, scheduling, mutex vs semaphore, deadlock, paging, virtual memory and page replacement. For deeper study, pair it with a standard textbook like Silberschatz.
Do the notes cover mutex vs semaphore?
Yes, with definitions, the wait() and signal() code, a comparison table, the ownership difference and the classic producer-consumer solution.
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