Week 3

 Week 3 (7/9-7/15)

What did I learn this week in CST 334?

I learned different concepts this week. The book and lectures teach how computers use virtual memory to let each program act like it has its own private memory, even though all programs share the same physical RAM. This is done through a system of address translation, where virtual addresses (used by programs) are converted into physical addresses (used by the hardware).  One method is base-and-bounds, where each process is assigned a block of memory, and hardware checks ensure it stays within limits. A more flexible method is segmentation, which breaks memory into parts like code, stack, and heap with their own base and size, allowing for better protection and organization.

The book, lecture videos, and assignment for this week include simulations showing how virtual addresses are split and mapped to physical memory, making concepts like translation clearer. They also explain address spaces, which are the ranges of addresses a process can use. Each process has its own address space to prevent interference. To manage memory efficiently, the operating system uses free space management techniques. These include first fit (choosing the first block big enough), best fit (choosing the smallest block that fits), and worst fit (choosing the largest block to avoid leaving tiny gaps). These strategies help reduce wasted memory and prevent fragmentation, when free memory is split into unusable pieces. The chapters and assignments also discuss how malloc() and free() in C are used to request and release memory manually, and the risks of doing so incorrectly, such as memory leaks. Overall, this week's content builds a strong foundation for understanding how the OS manages memory safely, efficiently, and fairly among processes.