标签：c++ linux 线程 文件系统 源码
proc文件系统下的
/proc/stat,
/proc/meminfo,
/proc/<pid>/status,
/proc/<pid>/stat
总的cpu时间totalCpuTime = user + nice+ system + idle + iowait + irq + softirq + stealstolen + guest
进程的总Cpu时间processCpuTime = utime + stime + cutime + cstime
占用内存的计算方法：pmem = VmRSS / MemTotal * 100
计算CPU占用的方法：
取一次processCpuTime1和totalCpuTime1;
间隔一段时间;
再取一次processCpuTime2和totalCpuTime2;
pcpu = 100 * (processCpuTime2 – processCpuTime1)/(totalCpuTime2 - totalCpuTime1);
//-----------------mytop.cpp------------------------
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include <string>
#include<unistd.h>
#include<fcntl.h>
#include<ctype.h>
#include <sys/types.h>
#include <dirent.h>
#include <errno.h>
#include <asm/page.h>
#include <vector>
#include <assert.h>
#include<iostream>
using namespace std;
#define CK_TIME 1
struct FileAttribute
{
string path;
string name;
unsigned long long size;
time_t modify_timestamp;
bool is_dir;
};
int EnumFile(vector<FileAttribute> &file_array, string _dir)
{
DIR* dir=opendir(_dir.c_str()); //(".")
if(dir == NULL)
return 0;
struct dirent* entry;
while((entry=readdir(dir)))
{
if( strcmp( entry->d_name,".") ==0 || strcmp( entry->d_name,"..") ==0 )
continue;
FileAttribute fi;
fi.name = entry->d_name;
fi.is_dir = false;
string path;
if(_dir=="/"||(_dir.rfind("/")+1)>=_dir.length())
path=_dir+fi.name;
else
path = _dir+"/"+fi.name;
struct stat statbuf;
if (stat( path.c_str(),&statbuf ) < 0)
{
closedir(dir);
printf("stat error ! message: %s\n",strerror(errno));
return 0;
}
if (S_ISDIR(statbuf.st_mode))
{
fi.is_dir = true;
}
fi.size = statbuf.st_size;
fi.modify_timestamp =statbuf.st_mtime;
fi.path = path;
file_array.push_back(fi);
}
closedir(dir);
return file_array.size();
}
char * skip_token(const char *p)
{
while (isspace(*p)) p++;
while (*p && !isspace(*p)) p++;
return (char *)p;
}
int get_sys_mem(char *mem)
{
int tm,fm,bm,cm,ts,fs;
char buffer[4096+1];
char sys_mem[1024];
int fd, len;
char *p;
//fd = open("/proc/meminfo", O_RDONLY);
if((fd = open("/proc/meminfo", O_RDONLY)) < 0)
{
perror("open /proc/meminfo file failed");
exit(1);
}
len = read(fd, buffer, sizeof(buffer)-1);
close(fd);
buffer[len] = ‘\0‘;
p = buffer;
p = skip_token(p);
tm = strtoul(p, &p, 10); /* total memory */
p = strchr(p, ‘\n‘);
p = skip_token(p);
fm= strtoul(p, &p, 10); /* free memory */
p = strchr(p, ‘\n‘);
p = skip_token(p);
bm= strtoul(p, &p, 10); /* buffer memory */
p = strchr(p, ‘\n‘);
p = skip_token(p);
cm= strtoul(p, &p, 10); /* cached memory */
for(int i = 0; i< 8 ;i++)
{
p++;
p = strchr(p, ‘\n‘);
}
p = skip_token(p);
ts= strtoul(p, &p, 10); /* total swap */
p = strchr(p, ‘\n‘);
p = skip_token(p);
fs= strtoul(p, &p, 10); /* free swap */
sprintf(mem,"Mem: %luk total,%luk used,%luk free,%luk buffer\nSwap: %luk total,%luk used, %luk free,%luk cached\n",
tm,tm-fm,fm,bm,ts,ts-fs,fs,cm);
//printf("%s\n",mem);
return tm;
}
int get_phy_mem(pid_t pid,char* ph)
{
char file[64] = {0};//文件名
FILE *fd; //定义文件指针fd
char line_buff[256] = {0}; //读取行的缓冲区
sprintf(file,"/proc/%d/status",pid);
//fd = fopen (file, "r");
if((fd = fopen (file, "r"))==NULL)
{
printf("Can‘t open file\n");
exit(1);
}
//获取vmrss:实际物理内存占用
int i;
char name1[32];//存放项目名称
int vmrss;//存放内存峰值大小
char name2[32];
int vmsize;
for (i=0;i<12;i++)
{
fgets (line_buff, sizeof(line_buff), fd);
}
fgets (line_buff, sizeof(line_buff), fd);
sscanf (line_buff, "%s %d", name2,&vmsize);
//fprintf (stderr, "====%s：%d====\n", name2,vmsize);
for (i=0;i<2;i++)
{
fgets (line_buff, sizeof(line_buff), fd);
}
fgets (line_buff, sizeof(line_buff), fd);//读取VmRSS这一行的数据,VmRSS在第15行
sscanf (line_buff, "%s %d", name1,&vmrss);
//fprintf (stderr, "====%s：%d====\n", name1,vmrss);
fclose(fd); //关闭文件fd
sprintf(ph,"VIRT=%dKB RES=%dKB",vmsize,vmrss);
//printf("=+=+=%s\n",ph);
return vmrss;
}
int get_process_time(pid_t pid,int tid)
{
char szStatStr[1024];
char pname[64];
char state;
int ppid,pgrp,session,tty,tpgid;
unsigned int flags,minflt,cminflt,majflt,cmajflt;
int utime,stime,cutime,cstime,counter,priority;
unsigned int timeout,itrealvalue;
int starttime;
unsigned int vsize,rss,rlim,startcode,endcode,startstack,kstkesp,kstkeip;
int signal,blocked,sigignore,sigcatch;
unsigned int wchan;
char file_stat [1024];
if(tid==0)
{
sprintf( file_stat,"/proc/%d/stat",pid );
}else if(tid!=-1)
{
sprintf( file_stat,"/proc/%d/task/%d/stat",pid,tid );
}
//printf("open file %s\n",file_stat);
FILE* fid;
//fid = fopen(file_stat,"r");
if((fid = fopen (file_stat, "r"))==NULL)
{
printf("Can‘t open file\n");
exit(1);
}
fgets(szStatStr,sizeof(szStatStr),fid);
fclose(fid);
//printf("+++szStatStr=%s\n",szStatStr);
sscanf (szStatStr, "%u", &pid);
char *sp, *t;
sp = strchr (szStatStr, ‘(‘) + 1;
t = strchr (szStatStr, ‘)‘);
strncpy (pname, sp, t - sp);
sscanf (t + 2, "%c %d %d %d %d %d %u %u %u %u %u %d %d %d %d %d %d %u %u %d %u %u %u %u %u %u %u %u %d %d %d %d %u",
/* 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33*/
&state,&ppid,&pgrp,&session,&tty,&tpgid,&flags,&minflt,&cminflt,&majflt,&cmajflt,&utime,&stime,&cutime,&cstime,&counter,
&priority,&timeout,&itrealvalue,&starttime,&vsize,&rss,&rlim,&startcode,&endcode,&startstack,
&kstkesp,&kstkeip,&signal,&blocked,&sigignore,&sigcatch,&wchan);
/*printf("-------%c %d %d %d %d %d %u %u %u %u %u -%d -%d -%d -%d %d %d %u %u %d %u %u %u %u %u %u %u %u %d %d %d %d %u",
state,ppid,pgrp,session,tty,tpgid,flags,minflt,cminflt,majflt,cmajflt,utime,stime,cutime,cstime,counter,
priority,timeout,itrealvalue,starttime,vsize,rss,rlim,startcode,endcode,startstack,
kstkesp,kstkeip,signal,blocked,sigignore,sigcatch,wchan);
*/
//printf("+++%lu %lu %lu %lu\n",utime,stime,cutime,cstime);
int p_cpu=utime+stime+cutime+cstime;
return p_cpu;
}
string GetCpuMem( size_t pid, string &cpu ,string &mem,int tid=0 )
{
FILE *fp;
char buf[128];
char tcpu[7];
char result[512];
char ccpu[256];
char cmem[256];
char process[1028];
unsigned int user,nice,sys,idle,iowait,irq,softirq,steal;
unsigned int all1,all2;
unsigned int us1,ni1,sy1,id1,io1,ir1,so1,st1;
unsigned int us2,ni2,sy2,id2,io2,ir2,so2,st2;
unsigned int p_cpu1,p_cpu2;
float usage,niage,syage,idage,ioage,irage,soage,stage;
//fp = fopen("/proc/stat","r");
if((fp = fopen ("/proc/stat", "r"))==NULL)
{
printf("Can‘t open file\n");
exit(1);
}
fgets(buf,sizeof(buf),fp);
sscanf(buf,"%s%d%d%d%d%d%d%d%d",tcpu,&user,&nice,&sys,&idle,&iowait,&irq,&softirq,&steal);
//printf("%s,%d,%d,%d,%d,%d,%d,%d,%d\n",tcpu,user,nice,sys,idle,iowait,irq,softirq,steal);
all1 = user+nice+sys+idle+iowait+irq+softirq+steal;
us1=user;ni1=nice;sy1=sys;id1=idle;
io1=iowait;ir1=irq;so1=softirq;st1=steal;
//=============================================
char file_dir[256];
sprintf(file_dir,"/proc/%d/task",pid);
string _dir=file_dir;
//printf("-----%s\n",file_dir);
vector<FileAttribute> file_array;
int file_sum=EnumFile(file_array,_dir);
unsigned int a[file_sum];
unsigned int b[file_sum];
unsigned int b2[file_sum];
int i=0;
if(tid==-1)
{
for(vector<FileAttribute>::iterator it=file_array.begin();it!=file_array.end();it++)
{
_dir=(*it).name;
//cout<<"_dir="<<_dir<<endl;
a[i]=atoi( _dir.c_str());
i++;
}
for(int j=0;j<file_sum;j++)
{
b[j]=get_process_time( pid,a[j]);
}
}else
{
p_cpu1= get_process_time( pid, tid);
}
//===========================================
/*第二次取数据*/
sleep(CK_TIME);
rewind(fp);
memset(buf,0,sizeof(buf));
tcpu[0] = ‘\0‘;
user=nice=sys=idle=iowait=irq=softirq=steal=0;
fgets(buf,sizeof(buf),fp);
sscanf(buf,"%s%d%d%d%d%d%d%d%d",tcpu,&user,&nice,&sys,&idle,&iowait,&irq,&softirq,&steal);
//printf("%s,%d,%d,%d,%d,%d,%d,%d,%d\n",tcpu,user,nice,sys,idle,iowait,irq,softirq,steal);
us2=user;ni2=nice;sy2=sys;id2=idle;
io2=iowait;ir2=irq;so2=softirq;st2=steal;
all2 = user+nice+sys+idle+iowait+irq+softirq+steal;
usage =(float)((us2-us1)+(ni2-ni1))/(all2-all1)*100 ;
syage=(float)((sy2-sy1)+(ir2-ir1)+(so2-so1))/(all2-all1)*100 ;
idage=(float)(id2-id1)/(all2-all1)*100;
niage=(float)(ni2-ni1)/(all2-all1)*100;
ioage=(float)(io2-io1)/(all2-all1)*100;
irage=(float)(ir2-ir1)/(all2-all1)*100;
soage=(float)(so2-so1)/(all2-all1)*100;
stage=(float)(so2-so1)/(all2-all1)*100;
if(tid==-1)
{
for(int j=0;j<file_sum;j++)
{
b2[j]=get_process_time( pid,a[j]);
}
}else
{
p_cpu2= get_process_time( pid, tid);
}
int NUM_PROCS = sysconf(_SC_NPROCESSORS_CONF);
//printf("======%d",NUM_PROCS);
float prcpu[file_sum];
float pcpu;
if(tid==-1)
{
for(int j=0;j<file_sum;j++)
{
prcpu[j]=(float)(b2[j]-b[j])/(all2-all1)*NUM_PROCS*100;
}
}else
{
pcpu = (float)(p_cpu2 - p_cpu1)/(all2-all1)*NUM_PROCS*100;
}
//printf("cpu(s): %.2f\% ,%.2f\% ,%.2f\% ,%.2f\% ,%.2f\% ,%.2f\% ,%.2f\% ,%.2f\% \n",
// usage,syage,niage,idage,ioage,irage,soage,stage);
sprintf(ccpu,"Cpu(s): %.2f%%us,%.2f%%sy,%.2f%%ni,%.2f%%id,%.2f%%wa,%.2f%%hi,%.2f%%si,%.2f%%st\n",
usage,syage,niage,idage,ioage,irage,soage,stage);
fclose(fp);
char ph[256];
long page_size = sysconf(_SC_PAGESIZE)>>10;
float pmem=(get_phy_mem(pid,ph)*page_size)/get_sys_mem(cmem)*100;
cpu=ccpu;
mem=cmem;
if(tid==-1)
{
int offset = 0;
for(int j=0;j<file_sum;j++)
{
//printf("PID=%d TID=%d %.2f%%CPU %.2f%%MEM %s\n",pid,a[j],prcpu[j],pmem,ph);
offset += sprintf(process+ offset,"PID=%d TID=%d %.2f%%CPU %.2f%%MEM %s\n",pid,a[j],prcpu[j],pmem,ph);
}
//printf("%s\n",process);
}else
{
sprintf(process,"PID=%d TID=%d %.2f%%CPU %.2f%%MEM %s",pid,tid,pcpu,pmem,ph);
//printf("PID=%d TID=%d %.2f%%CPU %.2f%%MEM %s\n",pid,tid,pcpu,pmem,ph);
}
//==================================================
sprintf(result,"%s%s%s",ccpu,cmem,process);
string s=result;
return s;
}
int main(int argc, char** argv)
{
int pid=0;
int tid=0;
string cpu,mem;
if( argc > 1 )
pid = atoi(argv[1]);
else{
pid = getpid();
}
if( argc > 2 )
tid = atoi(argv[2]);
//printf("pid=%d,tid=%d\n",pid,tid);
while(1)
{
cout<<"----------------------------"<<endl;
string s=GetCpuMem(pid,cpu,mem,tid);
cout<<s<<endl;
}
return 0;
}
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
编译：g++ -g -o mytop mytop.cpp
运行：./mytop (默认程序mytop进程的pid，tid默认为0)
./mytop pid (指定程序的pid，tid默认为0)
./mytop pid tid (指定程序的进程pid与及程序线程的tid)
./mytop pid -1 (指定程序的全部线程)
计算Linux系统和进程和线程的CPU及内存使用率(c++源码)
标签：c++ linux 线程 文件系统 源码
原文地址：http://blog.csdn.net/fengyelengfeng/article/details/41244359
