CPU Scheduling Algorithms Quiz

Scheduling Algorithms

• Windows uses a priority-based preemptive scheduling algorithm that adjusts thread priorities dynamically.
• Linux employs a Weighted Fair Queueing algorithm, balancing priorities while ensuring fairness among processes.
• Solaris implementing a variety of scheduling classes, including timesharing and real-time scheduling, to handle different process requirements.

Main Concerns of Process Execution

• The primary concern is ensuring efficient CPU utilization and minimizing process wait time while maintaining system responsiveness.

CPU–I/O Burst Cycle

• The CPU–I/O Burst Cycle alternates between CPU burst (computation phases) and I/O burst (input/output operations).
• Understanding this cycle helps optimize resource allocation and scheduling.

CPU Burst Distribution

• The exponential distribution is of particular interest as it models CPU burst times effectively, influencing scheduling decisions and performance.

Multiprogramming and CPU Utilization

• Multiprogramming maximizes CPU utilization by keeping several processes in memory, allowing the CPU to switch among processes when one is waiting for I/O, thus reducing idle time.

CPU Scheduling Triggers

• Events such as process arrival, completion, or transitions to waiting states trigger CPU scheduling decisions to optimize overall system performance.

Issues with Preemptive Scheduling

• Preemptive scheduling can lead to race conditions when multiple processes attempt to access shared data simultaneously, potentially resulting in inconsistent data states.

Circumstances for Nonpreemptive Scheduling

• Nonpreemptive scheduling occurs when processes voluntarily yield control once they complete their CPU bursts or enter waiting states, allowing for a predictable execution flow.

Role of the Dispatcher Module

• The dispatcher module is responsible for switching the CPU from one process to another, saving and loading context, and ensuring smooth transitions between processes.

CPU Utilization Criterion

• The criterion for maximizing CPU utilization focuses on minimizing idle time by efficiently allocating CPU cycles to processes, promoting maximum throughput.