From 5f2763dd443292aba4186aeccf864d8df38c3d35 Mon Sep 17 00:00:00 2001 From: russelltao Date: Thu, 7 Nov 2019 14:56:47 +0800 Subject: [PATCH] add readme --- 1-cpu_cache/branch_predict/README.md | 53 +++++++++ 1-cpu_cache/cpu_migrate/README.md | 103 ++++++++++++++++++ 1-cpu_cache/traverse_1d_array/README.md | 49 +-------- .../traverse_1d_array/traverse_1d_array.java | 40 ------- 4 files changed, 157 insertions(+), 88 deletions(-) create mode 100644 1-cpu_cache/branch_predict/README.md create mode 100644 1-cpu_cache/cpu_migrate/README.md delete mode 100644 1-cpu_cache/traverse_1d_array/traverse_1d_array.java diff --git a/1-cpu_cache/branch_predict/README.md b/1-cpu_cache/branch_predict/README.md new file mode 100644 index 0000000..be498a4 --- /dev/null +++ b/1-cpu_cache/branch_predict/README.md @@ -0,0 +1,53 @@ +## 1. 验证环境 +* 操作系统: CentOS7.0 +* CPU: Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz +* GCC-C++: 4.8.5 +* JAVA: 1.8.0 +* Python: 2.7.5 +## 2. C++程序branch_predict.cpp +### a. 编译程序 +#### 安装编译依赖的软件 +如Linux中需要安装gcc-c++，CentOS中可用`yum install gcc-c++`安装，Ubuntu中可用`apt-get install gcc-c++` +#### 编译程序 +`g++ branch_predict.cpp -o branch_predict` +### b. 运行验证 +#### 准备随机数组与排序好的数组 +`./branch_predict -g` +该命令会在当前目录下生成随机数组rand.array文件和有序数组sort.array文件 +#### 遍历随机数组 +`./branch_predict -s` +消耗时间（毫秒）：1000 +#### 遍历有序数组 +`./branch_predict -f` +消耗时间（毫秒）：350 +#### 遍历随机数组 +`perf stat -e cache-references,cache-misses,instructions,cycles,L1-dcache-load-misses,L1-dcache-loads ./branch_predict -` +``` + Performance counter stats for './branch_predict -s': + + 1,504,222,463 instructions # 0.49 insn per cycle + 3,084,103,065 cycles + 84,992 L1-icache-load-misses + 67,153,573 branch-load-misses + 273,893,334 branch-loads + + 1.040296121 seconds time elapsed + + 0.987243000 seconds user + 0.053060000 seconds sys +``` +#### 遍历有序数组 +`perf stat -e cache-references,cache-misses,instructions,cycles,L1-dcache-load-misses,L1-dcache-loads ./branch_predict -f` +* 输出结果： +``` + 1,501,478,360 instructions # 1.27 insn per cycle + 1,180,637,963 cycles + 49,351 L1-icache-load-misses + 27,282 branch-load-misses + 273,404,227 branch-loads + + 0.404512198 seconds time elapsed + + 0.352686000 seconds user + 0.051845000 seconds sys +``` diff --git a/1-cpu_cache/cpu_migrate/README.md b/1-cpu_cache/cpu_migrate/README.md new file mode 100644 index 0000000..516a6a3 --- /dev/null +++ b/1-cpu_cache/cpu_migrate/README.md @@ -0,0 +1,103 @@ +## 1. 验证环境 +* 操作系统: CentOS7.0 +* CPU: Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz +* GCC-C++: 4.8.5 +* JAVA: 1.8.0 +* Python: 2.7.5 +## 2. C++程序traverse_2d_array.cpp +### a. 编译程序 +#### 安装编译依赖的软件 +如Linux中需要安装gcc-c++，CentOS中可用`yum install gcc-c++`安装，Ubuntu中可用`apt-get install gcc-c++` +#### 编译程序 +`g++ traverse_2d_array.cpp -o traverse_2d_array` +### b. 运行验证 +#### 使用array[i][j]遍历数组 +`./traverse_2d_array -f` +消耗时间（毫秒）：10 +#### 使用array[j][i]遍历数组 +`./traverse_2d_array -s` +消耗时间（毫秒）：70 +### c. 使用perf验证缓存命中率 +#### 使用array[i][j]遍历数组 +`perf stat -e cache-references,cache-misses,instructions,cycles,L1-dcache-load-misses,L1-dcache-loads ./traverse_2d_array -f` +* 输出结果： +``` + Performance counter stats for './traverse_2d_array -f': + + 147,927 cache-references (80.14%) + 13,215 cache-misses # 8.933 % of all cache refs (65.49%) + 54,454,827 instructions # 1.43 insn per cycle (85.11%) + 38,197,267 cycles (85.09%) + 161,503 L1-dcache-load-misses # 0.90% of all L1-dcache hits (85.09%) + 18,035,307 L1-dcache-loads (84.19%) + + 0.020651344 seconds time elapsed + + 0.018625000 seconds user + 0.002069000 seconds sys +``` +#### 使用array[j][i]遍历数组 +`perf stat -e cache-references,cache-misses,instructions,cycles,L1-dcache-load-misses,L1-dcache-loads ./traverse_2d_array -s` +* 输出结果： +``` + Performance counter stats for './traverse_2d_array -s': + + 4,341,186 cache-references (83.01%) + 13,974 cache-misses # 0.322 % of all cache refs (66.03%) + 55,245,646 instructions # 0.25 insn per cycle (83.01%) + 218,787,967 cycles (83.00%) + 4,308,394 L1-dcache-load-misses # 23.79% of all L1-dcache hits (83.86%) + 18,112,753 L1-dcache-loads (84.10%) + + 0.082950118 seconds time elapsed + + 0.079066000 seconds user + 0.003953000 seconds sys +``` +## 3. Java程序 +### a. 编译程序 +`javac traverse_2d_array.java` +### b.运行验证 +#### 使用array[i][j]遍历数组 +`java traverse_2d_array -f` +消耗时间（毫秒）：20 +#### 使用array[j][i]遍历数组 +`java traverse_2d_array -s` +消耗时间（毫秒）：100 +### c. 使用perf验证缓存命中率 +#### 使用array[i][j]遍历数组 +`perf stat -e cache-references,cache-misses,instructions,cycles,L1-dcache-load-misses,L1-dcache-loads ./traverse_2d_array -f` +* 输出结果： +``` + Performance counter stats for 'java traverse_2d_array -f': + + 6,379,138 cache-references (80.62%) + 866,578 cache-misses # 13.585 % of all cache refs (68.93%) + 459,726,039 instructions # 1.51 insn per cycle (85.22%) + 303,673,757 cycles (85.69%) + 5,270,707 L1-dcache-load-misses # 3.96% of all L1-dcache hits (81.64%) + 133,211,743 L1-dcache-loads (83.13%) + + 0.126089887 seconds time elapsed + + 0.122353000 seconds user + 0.047877000 seconds sys +``` +#### 使用array[j][i]遍历数组 +`perf stat -e cache-references,cache-misses,instructions,cycles,L1-dcache-load-misses,L1-dcache-loads ./traverse_2d_array -s` +* 输出结果： +``` + Performance counter stats for 'java traverse_2d_array -s': + + 42,441,956 cache-references (80.21%) + 872,336 cache-misses # 2.055 % of all cache refs (66.61%) + 386,326,280 instructions # 0.71 insn per cycle (84.29%) + 544,411,061 cycles (85.01%) + 38,884,991 L1-dcache-load-misses # 32.48% of all L1-dcache hits (85.24%) + 119,711,464 L1-dcache-loads (82.94%) + + 0.192838747 seconds time elapsed + + 0.200693000 seconds user + 0.052919000 seconds sys +``` \ No newline at end of file diff --git a/1-cpu_cache/traverse_1d_array/README.md b/1-cpu_cache/traverse_1d_array/README.md index 5f455d0..2d12074 100644 --- a/1-cpu_cache/traverse_1d_array/README.md +++ b/1-cpu_cache/traverse_1d_array/README.md @@ -31,7 +31,7 @@ 26,230 cache-misses # 7.882 % of all cache refs (67.17%) 111,702,471 instructions # 1.61 insn per cycle (83.59%) 69,498,357 cycles (83.57%) - ** 250,109 L1-dcache-load-misses # 0.43% of all L1-dcache hits (83.58%) ** + 250,109 L1-dcache-load-misses # 0.43% of all L1-dcache hits (83.58%) 58,115,659 L1-dcache-loads (82.72%) 0.030938059 seconds time elapsed @@ -71,51 +71,4 @@ 0.158064000 seconds user 1.736704000 seconds sys -``` -## 3. Java程序 -### a. 编译程序 -`javac traverse_1d_array.java` -### b.运行验证 -#### 使用array[i][j]遍历数组 -`java traverse_1d_array -f` -消耗时间（毫秒）：20 -#### 使用array[j][i]遍历数组 -`java traverse_1d_array -s` -消耗时间（毫秒）：100 -### c. 使用perf验证缓存命中率 -#### 使用array[i][j]遍历数组 -`perf stat -e cache-references,cache-misses,instructions,cycles,L1-dcache-load-misses,L1-dcache-loads ./traverse_1d_array -f` -* 输出结果： -``` - Performance counter stats for 'java traverse_2d_array -f': - - 6,379,138 cache-references (80.62%) - 866,578 cache-misses # 13.585 % of all cache refs (68.93%) - 459,726,039 instructions # 1.51 insn per cycle (85.22%) - 303,673,757 cycles (85.69%) - 5,270,707 L1-dcache-load-misses # 3.96% of all L1-dcache hits (81.64%) - 133,211,743 L1-dcache-loads (83.13%) - - 0.126089887 seconds time elapsed - - 0.122353000 seconds user - 0.047877000 seconds sys -``` -#### 使用array[j][i]遍历数组 -`perf stat -e cache-references,cache-misses,instructions,cycles,L1-dcache-load-misses,L1-dcache-loads ./traverse_1d_array -s` -* 输出结果： -``` - Performance counter stats for 'java traverse_2d_array -s': - - 42,441,956 cache-references (80.21%) - 872,336 cache-misses # 2.055 % of all cache refs (66.61%) - 386,326,280 instructions # 0.71 insn per cycle (84.29%) - 544,411,061 cycles (85.01%) - 38,884,991 L1-dcache-load-misses # 32.48% of all L1-dcache hits (85.24%) - 119,711,464 L1-dcache-loads (82.94%) - - 0.192838747 seconds time elapsed - - 0.200693000 seconds user - 0.052919000 seconds sys ``` \ No newline at end of file diff --git a/1-cpu_cache/traverse_1d_array/traverse_1d_array.java b/1-cpu_cache/traverse_1d_array/traverse_1d_array.java deleted file mode 100644 index 71d28ce..0000000 --- a/1-cpu_cache/traverse_1d_array/traverse_1d_array.java +++ /dev/null @@ -1,40 +0,0 @@ -import java.util.Date; - - -public class traverse_1d_array{ - public static void main(String args[]){ - int ch; - int TESTN = 4096; - boolean slowMode = false; - for (String arg : args) { - if ("-f".equals(arg)) { - slowMode = false; - break; - } else if ("-s".equals(arg)) { - slowMode = true; - break; - } - } - - char [][]arr = new char[TESTN][TESTN]; - Date start = new Date(); - if (!slowMode) { - for(int i = 0; i < TESTN; i++) { - for(int j = 0; j < TESTN; j++) { - //arr[i][j]是连续访问的 - arr[i][j] = 0; - } - } - } else { - for(int i = 0; i < TESTN; i++) { - for(int j = 0; j < TESTN; j++) { - //arr[j][i]是不连续访问的 - arr[j][i] = 0; - } - } - } - - System.out.println(new Date().getTime()-start.getTime()); - } -} - -- GitLab