CST 334 - Week 1

The First Week

Here we go! Introduction to Operating Systems has officially begun. My mentor told me that this would be the most difficult class in my journey to a bachelor's degree, but Dr. Tao disagrees. Since the latter is the architect of the program, I will take his word for it. Nonetheless, I have been mentally preparing for this class for awhile and I am ready to knock it out. I am extremely giddy about learning operating systems.

An Abstraction of Hardware

This week I learned that an operating system is an abstraction of the hardware. The hardware itself has limitations, but an operating system helps overcome these limitations by virtualizing everything (CPU, Disk, RAM) and becoming a resource manager, delicately balancing all 3. 

Virtual Memory is probably the most well known. The operating system creates an illusion of unlimited memory for an application by using both the RAM and Disk as memory locations (storing frequently accessed values in RAM and lesser-accessed values on the disk temporarily). 

Virtualization of the CPU allows multiple processes to take turns running on the processor, creating an illusion of multiple processors. This is accomplished through process scheduling, which allows processes which are waiting on something else (like input) to wait in a queue while another process takes a turn on the CPU. 

Finally, virtualization of the disk occurs in the form of a file system. There is no file system on the physical drive, so the operating system must read/write the disk in a certain way (by following the specifications of the file system).