代碼來自網絡，部分修改，親測絕對可用
C++:
#include<stdio.h> #include<stdlib.h> #include<string.h> #include <iostream> #include <unistd.h> using namespace std; typedef struct MEMPACKED //定義一個mem occupy的結構體 { char name1[20]; //定義一個char類型的數組名name有20個元素 unsigned long MemTotal; char name2[20]; unsigned long MemFree; char name3[20]; unsigned long Buffers; char name4[20]; unsigned long Cached; char name5[20]; unsigned long SwapCached; }MEM_OCCUPY; //proc/stat文件結構 //cpu 633666 46912 249878 176813696 782884 2859 19625 0 //cpu0 633666 46912 249878 176813696 782884 2859 19625 0 //intr 5812844 //ctxt 265816063 //btime 1455203832 //processes 596625 //procs_running 1 //procs_blocked 0 typedef struct CPUPACKED //定義一個cpu occupy的結構體 { char name[20]; //定義一個char類型的數組名name有20個元素 unsigned int user; //定義一個無符號的int類型的user unsigned int nice; //定義一個無符號的int類型的nice unsigned int system;//定義一個無符號的int類型的system unsigned int idle; //定義一個無符號的int類型的idle unsigned int lowait; unsigned int irq; unsigned int softirq; }CPU_OCCUPY; void get_memoccupy(MEM_OCCUPY *mem) //對無類型get函數含有一個形參結構體類弄的指針O { FILE *fd; char buff[256]; MEM_OCCUPY *m; m = mem; fd = fopen("/proc/meminfo", "r"); //MemTotal: 515164 kB //MemFree: 7348 kB //Buffers: 7892 kB //Cached: 241852 kB //SwapCached: 0 kB //從fd文件中讀取長度為buff的字符串再存到起始地址為buff這個空間里 fgets(buff, sizeof(buff), fd); sscanf(buff, "%s %lu ", m->name1, &m->MemTotal); fgets(buff, sizeof(buff), fd); sscanf(buff, "%s %lu ", m->name2, &m->MemFree); fgets(buff, sizeof(buff), fd); sscanf(buff, "%s %lu ", m->name3, &m->Buffers); fgets(buff, sizeof(buff), fd); sscanf(buff, "%s %lu ", m->name4, &m->Cached); fgets(buff, sizeof(buff), fd); sscanf(buff, "%s %lu", m->name5, &m->SwapCached); fclose(fd); //關閉文件fd } int get_cpuoccupy(CPU_OCCUPY *cpust) //對無類型get函數含有一個形參結構體類弄的指針O { FILE *fd; char buff[256]; CPU_OCCUPY *cpu_occupy; cpu_occupy = cpust; fd = fopen("/proc/stat", "r"); fgets(buff, sizeof(buff), fd); sscanf(buff, "%s %u %u %u %u %u %u %u", cpu_occupy->name, &cpu_occupy->user, &cpu_occupy->nice, &cpu_occupy->system, &cpu_occupy->idle, &cpu_occupy->lowait, &cpu_occupy->irq, &cpu_occupy->softirq); fclose(fd); return 0; } void cal_cpuoccupy(CPU_OCCUPY *o, CPU_OCCUPY *n) { unsigned long od, nd; double cpu_use = 0; od = (unsigned long)(o->user + o->nice + o->system + o->idle + o->lowait + o->irq + o->softirq);//第一次(用戶+優先級+系統+空閑)的時間再賦給od nd = (unsigned long)(n->user + n->nice + n->system + n->idle + n->lowait + n->irq + n->softirq);//第二次(用戶+優先級+系統+空閑)的時間再賦給od double sum = nd - od; double idle = n->idle - o->idle; cpu_use = idle / sum; idle = n->user + n->system + n->nice - o->user - o->system - o->nice; cpu_use = idle / sum; printf("%.3f\n",cpu_use); } int main( int argc, char **argv ) { MEM_OCCUPY mem_stat; CPU_OCCUPY cpu_stat1; CPU_OCCUPY cpu_stat2; //獲取內存 //(MemTotal - MemFree)/ MemTotal get_memoccupy((MEM_OCCUPY *)&mem_stat); //printf(" [MemTotal] = %lu \n [MemFree] = %lu \n [Buffers] = %lu \n [Cached] = %lu \n [SwapCached] = %lu \n", mem_stat.MemTotal, mem_stat.MemFree, mem_stat.Buffers, mem_stat.Cached, mem_stat.SwapCached); printf("%.3f\n", mem_stat.MemFree * 1.0 / ( mem_stat.MemTotal * 1.0 ) ); //第一次獲取cpu使用情況 get_cpuoccupy((CPU_OCCUPY *)&cpu_stat1); usleep(100000); //第二次獲取cpu使用情況 get_cpuoccupy((CPU_OCCUPY *)&cpu_stat2); //計算cpu使用率 cal_cpuoccupy((CPU_OCCUPY *)&cpu_stat1, (CPU_OCCUPY *)&cpu_stat2); return 0; }
編譯
g++ get.cpp -o get
運行
[root@xxxxxxx ]# ./get
0.117
1.000
[root@xxxxxxx ]# ./get
0.119
0.000
上方的數值代表 內存空閑 / 內存總數
下方的數值代表 CPU占用率
詳細解釋：
https://blog.csdn.net/nineday/article/details/1928847
計划搭建一個簡易版的分布式集群...
一台主服務器，一台高配的數據庫服務器，n 台計算服務器
（1）在每台計算服務器中，寫一個定時任務，每隔 1 s 觸發一個PHP程序，該PHP將觸發上方的CPP程序，獲得服務器狀態，更新DATABASE中的服務器狀態表
（2）主服務器將獲得客戶端的請求，插入DATABASE中的消息隊列表
（3）主服務器中將寫一個servlet 定時函數，每隔 0.5 s 輪詢消息隊列表，一旦發現有新的消息請求集合或個體，則將該消息集合轉換成所封裝對象的隊列
（4）從前往后掃描隊列，每次選定 DATABASE中空閑資源最大的 一台計算服務器，發送一個包含JSON格式對象的HTTP請求
（5）計算服務器接收到HTTP請求后，將展開計算，計算完成后，更新DATABASE中的數據字段
（6）客戶端AJAX 0.5s 輪詢DATABASE，直到完成計算服務器完成計算
【上方集群中，采用 jsp + servlet 實現 java 后台。。。。。。得抓緊學習spring大家族啊，被技術限制住了......雖然servlet本身是單實例多線程的】
主服務器 servlet多線程 --- 任務隊列 --- 分布式並行計算 --- 計算服務器 servlet多線程
不知道並發咋樣。。。第一次碰分布式和並發這塊...
如果有大佬可以指點下，會非常感謝的！！！！！！