Linux threads occupy high CPU location analysis

Today, my friend asked me a Linux program CPU consumption limit, how to analyze,

High CPU consumption, simulating high CPU usage

The first piece of code:

1#include <iostream>2#include <thread>3#include <vector>4 5 6 intMainintargcChar**argv) {7   8Std::vector<std::thread>test_threads;9      for(inti =0; I <9; i++){Ten Test_threads.push_back (Std::thread ([]{ One      while(1){ AStd::this_thread::sleep_for (Std::chrono::milliseconds ( -)); -     } -       })); the     } - Test_threads.push_back (Std::thread ([]{ -        while(1){ -std::cout<<"CPU"<<Std::endl; +       } -     })); +      A      for(Auto &x:test_threads) { at X.join (); -     } -      -     return 0; -}

The 10th thread does not sleep, it will monopolize the process of the time slice, resulting in high CPU utilization,

Now we need to locate 10th.

First step: Top View program Process ID

Step two: Top-h-P 96263 locates CPU-intensive thread IDs

Step three: Use Pstack 96263 or strace-f-P 96263 to locate the thread stack

Strace-f-P 96263

Linux threads occupy high CPU location analysis