operating-system-visualization

name	operating-system-visualization
description	Use this skill whenever the user wants visual learning for operating systems, process states, CPU scheduling, Gantt charts, synchronization, semaphore/PV problems, deadlock, Banker's algorithm, memory management, paging, address translation, page replacement, file systems, disk scheduling, or 408 OS review.
allowed-tools	file_read, file_write

Operating System Visualization Skill

Create visual explanations for operating system mechanisms. The goal is to make queues, states, resources, and address mappings observable.

Use For

• process/thread state transition and scheduling queues;
• FCFS, SJF, priority, RR, HRRN scheduling and Gantt charts;
• semaphore/PV, producer-consumer, readers-writers, dining philosophers;
• deadlock conditions, resource allocation graphs, Banker's algorithm;
• paging, segmentation, virtual memory, TLB, page table translation;
• page replacement: OPT, FIFO, LRU, Clock;
• file allocation, directory structure, free-space management;
• disk scheduling: FCFS, SSTF, SCAN, C-SCAN.

Output Modes

Topic	Preferred visual
Scheduling	timeline/Gantt chart + ready queue per time
PV problem	constraint graph + semaphore table + pseudocode
Deadlock	resource allocation graph + request/available table
Address translation	virtual address split + page table/TLB + physical address
Page replacement	frame table per reference + fault markers
Disk scheduling	cylinder line + head movement path

Bundled Template

Choose the closest bundled template:

• assets/templates/os-stepper.html - process states, CPU scheduling, Gantt charts, disk scheduling, queue-based simulations.
• assets/templates/page-replacement.html - FIFO/LRU/OPT/Clock page replacement and frame tables.
• assets/templates/banker-matrix.html - Banker's algorithm, safe sequence, deadlock avoidance matrices.

Replace DATA.steps or the relevant DATA fields with the user's scheduling, page replacement, deadlock, or disk scheduling data. Keep the queue/matrix/table panels and exam-answer note unless the task is intentionally static.

Follow the shared UI standard in /skills/cs-course-learning/references/visual-template-ui.md when available: learning-workbench layout, stable controls, state table, step inspector, and exam-transfer panel.

Research-Informed Design Patterns

Use patterns from OS teaching simulators:

• accept custom datasets: processes, arrival times, burst times, time quantum, priorities, page reference strings, resource matrices;
• show both visualization and calculation table;
• include Gantt charts for scheduling;
• include Allocation/Max/Need/Available matrices for Banker's algorithm;
• include frame tables and page-fault markers for page replacement;
• include test mode or quick-check questions after the simulation.

Topic Coverage Checklist

For 408/期末复习, cover these families when relevant:

• process/thread model: states, PCB, context switch, IPC;
• scheduling: FCFS, SJF, SRTF, priority, RR, HRRN;
• synchronization: semaphore, mutex, monitor concept, producer-consumer, readers-writers;
• deadlock: conditions, prevention, avoidance, detection, Banker's algorithm;
• memory: contiguous allocation, paging, segmentation, TLB, virtual memory;
• page replacement: OPT, FIFO, LRU, Clock/second chance;
• file/I/O: file allocation, directory, free space, disk scheduling, interrupt/DMA.

Required Structure

• Show current state, next event, and why the transition occurs.
• Keep tables synchronized with animations.
• Include formulas for turnaround time, waiting time, page-fault count, or seek distance when relevant.
• Include an exam-answer panel that shows what to write in a paper solution.
• Include user-editable input panels when generating a learning simulator rather than solving one fixed problem.

Accuracy Rules

• Ask for missing scheduling parameters: arrival time, service time, time quantum, priority rule.
• For PV problems, identify shared resources, mutually exclusive sections, and precedence constraints before writing code.
• For page replacement, state the initial frame state and tie-breaking rule.
• For disk scheduling, state current head position, direction, and request queue.
• For Banker's algorithm, show Work/Finish and safe sequence step by step.

Coordination

• Use technical-diagram-skill for state machines, resource allocation graphs, page-table diagrams, and scheduling timelines.
• Use learning-visualization-skill for interactive HTML pages with step controls.
• Use cs-course-learning for broader OS learning and 408 strategy.