DISK SCHEDULING | OPERATING SYSTEM | LECTURE 03 BY MS MILI SRIVASTAVA | AKGEC

DISK SCHEDULING | OPERATING SYSTEM | LECTURE 03 BY MS MILI SRIVASTAVA | AKGEC

by Ms. Mili Srivastava

Formal & Physical Sciences Computing & Cybersecurity UComputing and Information TechnologyULOperating systems
🎙 Ms. Mili Srivastava 👥 22K 📅 October 12, 2025 ⏱ 18 min 👁 104 📄 tutorial 🧭 2026-08-16
Available in: English (current) Français

Keywords

disk schedulingFCFSSSTFSCANLOOK

Summary

This lecture by Ms. Mili Srivastava from AKGEC introduces disk scheduling algorithms in operating systems. It begins with the architecture of magnetic disks, explaining tracks, sectors, and the read/write head. The need for disk scheduling is motivated by the goal of efficient disk I/O. The lecture covers four main algorithms: FCFS (First Come First Served), SSTF (Shortest Seek Time First), SCAN (elevator algorithm), and LOOK. For each, it explains the principle, advantages, disadvantages, and provides a numerical example to illustrate the seek time calculations. The lecture emphasizes the importance of seek time as a major factor in disk performance. The presentation is didactic, aimed at B.Tech and MCA students, and includes step-by-step problem-solving. The instructor also mentions C-SCAN and C-LOOK but does not detail them. The lecture concludes with a comparison of the algorithms based on criteria like starvation and efficiency.

141 words

Critical Evaluation

Value of the Information & Strength of the Argument

The lecture provides a solid foundational understanding of disk scheduling algorithms, with clear explanations and worked examples that illustrate the mechanics of each algorithm. The argumentation is straightforward, focusing on the operational logic of each method. However, the presentation lacks depth in comparing the algorithms’ performance metrics beyond seek time, and the discussion of C-SCAN and C-LOOK is superficial. The examples are helpful but contain minor arithmetic errors, which slightly undermine the pedagogical value. Overall, the content is valuable for beginners but does not offer advanced insights or critical analysis.

Scientific Rigor, Source Quality, Title Accuracy

The lecture is based on standard operating systems concepts, but no explicit sources are cited within the video. The description provides links to the institution’s website and a playlist, but these are not specific references. The title accurately reflects the content. The presentation is informal, with some inaccuracies in terminology (e.g., ‘SSTF’ is defined as ‘Shortest Time First’ instead of ‘Shortest Seek Time First’) and calculations, which reduces the scientific rigor. The lack of citations to authoritative textbooks or papers is a notable weakness.

189 words

Title / Content Match

The title accurately reflects the content, which is a lecture on disk scheduling algorithms in operating systems.

Quality & Reliability

7/10

The lecture provides a clear and structured introduction to disk scheduling algorithms, with numerical examples. However, the presentation is informal, with some inaccuracies in terminology and calculations, and lacks citations to authoritative sources.

Key Moments

Markers derived by PSI from the transcript: the creator did not define chapters.

Cited Sources

Concurring Sources

Contribution & Novelties

The lecture offers a clear, step-by-step introduction to disk scheduling algorithms, which is particularly useful for students new to the topic. It provides worked numerical examples that illustrate the calculation of total seek time for FCFS, SSTF, SCAN, and LOOK. The main contribution is pedagogical, making complex concepts accessible. However, it does not introduce novel ideas or advanced optimizations.

Pour aller plus loin :

105 words

Radar Profile

The radar profile shows moderate scores across all dimensions, indicating a balanced but not exceptional lecture. The highest score is in quantity of information, reflecting the coverage of multiple algorithms, while the lowest is in technical level, suggesting the content is introductory.

Reliability 6/10