I have two threads that work the producer and consumer sides of a std::queue. The queue isn't often full, so I'd like to avoid the consumer grabbing the mutex that is guarding mutating the queue. I...

Ran the following in Visual Studio 2022 in release mode: #include <chrono> #include <mutex> #include <shared_mutex> #include <iostream> std::mutex mx; std::shared_mutex smx...

[thread.mutex.class]/3: [...] It is a standard-layout class ([class.prop]). What is the reason for this requirement?

Following static_assert passes in both gcc and clang trunk. #include<mutex> int main(){ static_assert(sizeof(std::mutex)==40); } Since x86 CPUs have 64 byte cache line I was expecting mutex...

I have two use cases. A. I want to synchronise access to a queue for two threads. B. I want to synchronise access to a queue for two threads and use a condition variable because one of the threads ...

The pthread_mutex_init() function returns a non-zero value when it fails to initialize the mutex, while the std::mutex class in C++11 has a constructor of noexcept. Say one chooses to implement a...

I am wondering how can std::atomic_ref be implemented efficiently (one std::mutex per object) for non-atomic objects as the following property seems rather hard to enforce: Atomic operations app...

I have a scenario where the shared memory area is exclusively accessed by two different processes. When I launch the processes, the first process successfully locks the mutex, updates the memory an...

It seems like CRITICAL_SECTION performance became worse on Windows 8 and higher. (see graphs below) The test is pretty simple: some concurrent threads do 3 million locks each to access a variable ...

Is the get_a() function safe for race-conditions or do I need to explicitly copy str_ as in get_b() in order to have a thread-safe function? class Class { public: auto get_a() -> std::st...

Take this simple function that increments an integer under a lock implemented by std::mutex: #include <mutex> std::mutex m; void inc(int& i) { std::unique_lock<std::mutex> lock(...

I have defined a class that has std::mutex my_mutex as its private member variable. But when I try to use it using lock_guard in a member function which is called from different threads, the compil...

I've seen most examples using std::mutex where the mutex is global. I was wondering is there any specific reason why this is done? I've had programs of my own where I don't do this, and simply pass...

I started using std::mutexes to stop a thread and wait for another thread to resume it. It works like this: Thread 1 // Ensures the mutex will be locked while(myWaitMutex.try_lock()); // Locks it...