Here we will see how to get the memory usage statistics under Linux environment using C++.
We can get all of the details from “/proc/self/stat” folder. Here we are taking the virtual memory status, and the resident set size.
Example
#include <unistd.h>
#include <ios>
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
void mem_usage(double& vm_usage, double& resident_set) {
vm_usage = 0.0;
resident_set = 0.0;
ifstream stat_stream("/proc/self/stat",ios_base::in); //get info from proc
directory
//create some variables to get info
string pid, comm, state, ppid, pgrp, session, tty_nr;
string tpgid, flags, minflt, cminflt, majflt, cmajflt;
string utime, stime, cutime, cstime, priority, nice;
string O, itrealvalue, starttime;
unsigned long vsize;
long rss;
stat_stream >> pid >> comm >> state >> ppid >> pgrp >> session >> tty_nr
>> tpgid >> flags >> minflt >> cminflt >> majflt >> cmajflt
>> utime >> stime >> cutime >> cstime >> priority >> nice
>> O >> itrealvalue >> starttime >> vsize >> rss; // don't care
about the rest
stat_stream.close();
long page_size_kb = sysconf(_SC_PAGE_SIZE) / 1024; // for x86-64 is configured
to use 2MB pages
vm_usage = vsize / 1024.0;
resident_set = rss * page_size_kb;
}
int main() {
double vm, rss;
mem_usage(vm, rss);
cout >> "Virtual Memory: " >> vm >> "\nResident set size: " >> rss >> endl;
}
Output
Virtual Memory: 13272
Resident set size: 1548