Arlon's CSUMB Blog

Arlon's CSUMB Intro to Operating Systems CST-334 Module 5 Learning Journal #5/#29 for the week Wed 07/20-Tues 07/27, year 2021 Journal spec: What to Write in your Journal Entry Write a 1 - 2 paragraph description of what you learned this fifth week in CST 334 Topic: Concurrency. Well concurrency is extremely interesting and C programming is extremely interesting and very challenging as usual. I really enjoy doing experiments with computer programs like this week's lab. Although I would say the lab as usual, much less than last week, was light on instructions and direction so it's hard to sometimes say exactly what is expected. Last week was much worse with regard to the lab but we also had a midterm this week which I bombed even though I have been studying extremely dilegently - I felt like the problems were from a different class - I'd really appreciate more practice problems - ok - actually - I'd really appreciate practice problems - I'd really apprecia...

Arlon's CSUMB Intro to Operating Systems CST-334 Module 4 Learning Journal #4/#28 for the week Wed 07/14-Tues 07/20, year 2021 This week in class we studied OS paradigms for memory management some more, which has to do with where the OS decides to put the actual memory while serving virtual memory addresses to programs and itself. Journal spec: write a 1 - 2 paragraph description of what you learned this fourth week in CST 334 Topic: Memory Virtualization: The way that the OS provides the illusion of private address spaces for each process is that there is an address translation with a page table each process generates - so that each program can get the same or relatively arbitrarily related labels for each process's virtual memory addresses while the OS translates the assigned labels to the actual RAM memory addresses using the page tables. The OS keeps a free list of available addresses so it knows where it can put what. There are various schemes used as to when to swap...

Arlon's CSUMB Intro to Operating Systems CST-334 Module 3 Learning Journal #3/#27 for the week Wed 07/07-Tues 07/13, year 2021 This week in class we studied OS paradigms for memory management which has to do with where the OS decides to put the actual memory while serving virtual memory addresses to programs and itself. There are several types of spaces for memory like for where the code goes (code space), where the procedure calls go (stack) and where variables and arrays go in memory (heap). Code is static because it's the code, stack space and heap space grow. So the book goes through the reasoning process of first putting them face-to-face growing inward with code space outside of them, then staggering inward with something called base and bounds and multiple programs fit in the same area, then base and bounds with segmentation based on a complicated segmentation process where the OS translates memory to different segments. In addition, after this week we are now intr...

Arlon's CSUMB Intro to Operating Systems CST-334 Module 2 Learning Journal #2/#26 for the week Wed 06/30-Tues 07/06, year 2021 This week in class we studied switching processes/threads and creating threads in C, and the theory aspects of how the kernel decides prioritization of threads with regard to when and how long they should be allowed to run, various partial strategies including round robin, FIFO, SJF, ending with multi-level feeback queue. We also started using makefiles for C programs. In threads study lab this week on top of testing variations of running child and parent threads I also found a way to turn a conditional inside-out with anonymous functions and a conditional operator, something like: /* Name: Arlon Arriola Date: 07/06/2021 Title: Lab2–threads/processes/child/parent–Alternative conditional structure Description: Study of alternative conditional structure for Lab 2–threads/processes/child/parent */ #include <stdio.h> /* printf, stderr */ ...