Homework for Chapter 15 of 《Operating Systems: Three Easy Pieces》: Relocation
December 3, 2025
root@C202511211157657:~# python3 relocation.py -s 1 ARG seed 1 ARG address space size 1k ARG phys mem size 16k Base-and-Bounds register information: Base : 0x0000363c (decimal 13884) Limit : 290 Virtual Address Trace VA 0: 0x0000030e (decimal: 782) --> PA or segmentation violation? VA 1: 0x00000105 (decimal: 261) --> PA or segmentation violation? VA 2: 0x000001fb […]
Homework for Chapter 9 of 《Operating Systems: Three Easy Pieces》: Lottery Scheduling
November 27, 2025
root@C202511211157657:~# tar xvzf HW-Lottery.tgz ./._lottery.py lottery.py ./._README-lottery README-lottery root@C202511211157657:~# python3 lottery.py ARG jlist ARG jobs 3 ARG maxlen 10 ARG maxticket 100 ARG quantum 1 ARG seed 0 Here is the job list, with the run time of each job: Job 0 ( length = 8, tickets = 75 ) Job 1 ( length = […]
Homework for Chapter 8 of 《Operating Systems: Three Easy Pieces》: MLFQ Scheduling
November 26, 2025
Select Homework for Chapter 8 of 《Operating Systems: Three Easy Pieces》: MLFQ Scheduling 1 root@C202511211157657:~# python3 mlfq.py -j 2 -M 0 -m 4 -n 2 -q 1 Here is the list of inputs: OPTIONS jobs 2 OPTIONS queues 2 OPTIONS allotments for queue 1 is 1 OPTIONS quantum length for queue 1 is 1 OPTIONS […]
Homework for Chapter 7 of 《Operating Systems: Three Easy Pieces》: Scheduling Basics
November 24, 2025
Concepts: the “response time” (the time a job spends waiting after arrival before first running); the “turnaround time” (the time it took to complete the job since first arrival); the total “wait time” (any time spent ready but not running). 1&2: I will simply combine both of 2 questions and draw some conclusion: root@C202511211157657:~\# ./scheduler.py […]
Homework for Chapter 6 of 《Operating Systems: Three Easy Pieces》: Direct Execution
November 23, 2025
We used Deepseek and Chatgpt to generate the code we use to measure. 1. Time cost of syscall: /** * System Call Overhead Measurement * Measures the time cost of a zero-byte read system call * Uses clock_gettime with MONOTONIC clock for precise timing * Binds process to single CPU for consistent measurements */ #define […]
Homework for Chapter 5 of 《Operating Systems: Three Easy Pieces》: Process API
November 22, 2025
1.Let’s see what if we change the variant v separately. root@C202511211157657:~# gcc main.c -o a.out root@C202511211157657:~# cat main.c #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <string.h> #include <fcntl.h> #include <sys/wait.h> int main(int argc, char *argv[]) { int v = 0; int rc = fork(); if (rc < 0) { // fork failed; exit fprintf(stderr, "fork […]
Homework for Chapter 4 of 《Operating Systems: Three Easy Pieces》: Process Intro
November 22, 2025
Note: I converted the original process-run.py using ChatGPT because I am too lasy to have another python on my server. I shared the file below as someone may also need one. Hopefully it won’t involve me into copyright issues, but if it did, please kindly tell me. process-run.py for Python3 And sure, if you’re not […]
Why We Need Operating System?
November 22, 2025
I made my own Gameboy emulator last year. Recently when I show it off to my friend, he asked me a thought-provoking question that I never came up with but should have: Does it need a operating system to run the game? Certainly, I knew the answer, because I had provide sufficient implement that a […]
Overwhelming Refactoring
November 21, 2025
Refactoring could be tempting, especially when you’ve finished reading a tech book, or some training course, you might feel yourself capable enough to get something done. After all, you can’t tolerate the shitty codes in the old big rotten code base anymore. The rush won’t stop until you finally strike into something. You might underestimate […]
Hello World!
November 21, 2025
My very first blog.

PixelMoe

PixelMoe.

Where I put my lousy things.