CST334 Week 2

The Computer Science Timeshare Presentation - Processes

In the second week of CST 334, we delved into the fundamental concept of processes within an operating system. A process, essentially, is a running program that the operating system manages. This week, we explored how the OS provides the illusion of many CPUs by using time-sharing techniques, allowing multiple processes to run seemingly concurrently on limited physical CPUs. We learned about the different states a process can occupy: running, ready, and blocked. A running process is actively executing instructions on the CPU, a ready process is prepared to run but is waiting for CPU availability, and a blocked process is waiting for an event, such as an I/O operation, to complete.

We also examined the mechanisms and policies the OS uses to handle context switching between processes. A voluntary context switch occurs when a process willingly yields the CPU, typically during I/O operations, while an involuntary context switch is forced by the OS, often due to time-sharing policies. These switches are crucial for maintaining system efficiency and ensuring that all processes receive fair CPU time.

In addition to process states and context switching, we covered process scheduling, focusing on metrics like turnaround and response times. Turnaround time is the total time taken from the submission of a process to its completion, while response time is the time from submission to the first response from the process. Although these concepts are fundamental to evaluating scheduling algorithms, I find calculating them somewhat challenging. Understanding these metrics is essential for assessing and optimizing the performance of different scheduling strategies, which is critical for efficient process management in operating systems.