Find Maximum Threads that Application Can Create on Linux using C++

Linux offers a powerful environment for concurrent programming, enabling developers to create multithreaded applications efficiently. However, there's a crucial aspect to consider: the maximum number of threads an application can create. Understanding this limit is essential for designing robust and scalable systems. This tutorial shows how to find the maximum threads that an application can create on Linux using C++.

The provided code utilizes the pthread library to create threads in a loop until an error occurs. Each thread executes a function that immediately exits. The main function maintains a count of successfully created threads, storing their identifiers in a vector. After all threads are created, it joins each thread, ensuring the main thread waits for their completion. Finally, it prints the count of created threads.

#include <iostream>
#include <vector>
#include <pthread.h>

void *threadFunction(void *) {
    pthread_exit(nullptr);
}

int main()
{
    std::vector<pthread_t> threads;
    unsigned long count = 0;
    while (true) {
        pthread_t tid;
        if (pthread_create(&tid, nullptr, threadFunction, nullptr) != 0) {
            break;
        }
        threads.push_back(tid);
        ++count;
    }

    for (pthread_t tid: threads) {
        pthread_join(tid, nullptr);
    }

    std::cout << count << std::endl;

    return 0;
}

Output example:

32743