學號：311551173 姓名：黃牧恩 Q1 What are the pros and cons of the three methods? Give an assumption about their performances. Method 1 Pros: 每一個thread只需要處理一個pixel Cons: 有些計算量小的thread只被使用一下，只有部分的thread會因為計算量較大而被使用較久，導致整體thread utilization較低

Q1.1: How do you control the number of MPI processes on each node? MPI run programs according to hostfile, it assign programs to machine in hostfile one-by-one. machine_1 machine_1 machine_2 If we're going to run 8 copies of the program and hostfile is defined as above, program_1 & program 2 will be assigned to machine_1, program_3 will be assigned to machine_2, program_4 will be assigned to machine_1, ...etc.

Q1: Is speedup linear in the number of threads used? In your writeup hypothesize why this is (or is not) the case? Refer to the graph above, the speedup is almost linear. Since all threads doing same thing, using more thread will reduce the loading of threads, which decrease the execution time linearly. Speedup is also almost linear too. Q2: How do your measurements explain the speedup graph you previously created?

contributed by <huang-me> 測驗一 (average) Solution 1 #include <stdint.h> uint32_t average(uint32_t a, uint32_t b) { return (a >> 1) + (b >> 1) + (a & b & 1); }

Contributed by < huang-me > 使用 atomic 與否差異 #include <stdatomic.h> int v = 0; atomic_bool v_ready = false; int bv; void *threadA() {

contributed by < huang-me > kecho 給定的 kecho 已使用 CMWQ，請陳述其優勢和用法 優勢： CMWQ 利用的 thread pool 的機制，大幅減少了創建 thread 的 overhead。 使用 unbounded thread 機制使得 thread 可以切換到 idle 的 CPU 上，增加系統資源的使用率。 引入 scheduling 機制資源不會被需要長時間的 thread 佔用。

contributed by < huang-me > twoSum Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target. struct hlist_node { struct hlist_node *next, **pprev; }; struct hlist_head { struct hlist_node *first; }; typedef struct { int bits; struct hlist_head *ht; } map_t; #define MAP_HASH_SIZE(bits) (1 << bits)

contributed by < huang-me > :::danger 注意作業書寫規範！ :notes: jserv ::: Prerequisites $ sudo apt install build-essential git clang-format aspell colordiff valgrind

contributed by <huang-me>, <OliveLake> :::info Expectation [x] RVVM ( https://github.com/LekKit/RVVM ) 同時支援 RV64 和 RV32，本課程著重於 RV32，請針對 RV32 準備相關的開發工具 (可重用 GNU Toolchain) [x] 留意 Linux 啟動流程: OpenSBI -> U-Boot -> Linux kernel -> userspace，請學習相關的背景知識，說明個別元件的作用，特別是 OpenSBI [ ] 準備 RV32 的 Linux 核心，你們可能會遭遇技術困難，記錄下來並嘗試排除 [ ] 說明 Linux 核心在 RV32/RVVM 啟動過程中，除了 CPU，還有哪些週邊的互動 (如中斷控制器和 timer)

contributed by: <huang-me> Rewrite Leetcode 191. Number of 1 Bits Write a function that takes an unsigned integer and returns the number of '1' bits it has (also known as the Hamming weight). C code int cntbit(int n) { if(n == 0) return 0; int cnt = 0;

Two Sum Approach 1: Iterate through all possible combinations, and check if the sum of combination is equal to target value, return index of two numbers. Time complexity: O($n^2$). For each element, we try to find its complement by looping through the rest of the array which takes O(n) time. Therefore, the time complexity is O($n^2$). vector<int> twoSum(vector<int>& nums, int target) { for(int i=0; i<nums.size(); i++) { for(int j=i+1; j<nums.size(); j++) { if(nums[i]+nums[j] == target) return {i, j};

Chrome add button to toggle GPU Command to start chrome with gpu-disabled open -a "Google Chrome" --args --load-extensions="${extensionPath}" --disable-gpu 可以在 chrome://gpu 中查看現在是否使用 GPU ==一般情況下如下圖：== 使用的 GPU 為 Intel(R) UHD Graphics 617