Recently when I was reading about lock-free programming, I came across "atomic operations". I started digging deep into it. All links explain how to write atomic operations and their usag...

I wanted to understand what does one mean by lock_free property of atomic variables in c++11. I did googled out and saw the other relevant questions on this forum but still having partial understan...

With reference to: Is rename() atomic? I'm asking something similar, but not quite the same, because what I want to know is is it safe to rely on the atomicty of rename() when using NFS? Here's a...

C++11 introduced the std::atomic<> template library. The standard specifies the store() and load() operations to atomically set / get a variable shared by more than one thread. My question is...

[atomics.types.operations] p23 says: bool compare_exchange_weak(T& expected, T desired, memory_order success, memory_order failure) noexcept; Effects: Retrieves the value in expected. It then ...

After a release operation A is performed on an atomic object M, the longest continuous subsequence of the modification order of M that consists of: Writes performed by the same thread that perfor...

Consider the following C code: #include <stdatomic.h> struct _opaque; typedef struct _opaque *opaque; struct container { _Atomic opaque x; }; struct container get_container(); void consume_...

Can atomic variables in C++11 be initialized globally? For example: std::atomic_int turnX = 5; int main() { /* ... */ } This fails with: error: deleted function ‘std::atomic<int>::atomic(co...

According to the C++17 standard, [support.signal], the atomic object should satisfy the following requirements to be used in a signal handler: [...], or f is a non-static member function invoked ...

I know that the -latomic flag is required for the atomic library to be linked in by GCC. However, for some reason std::atomic<int> doesn't require it to build build without latomic while stru...

I was looking at the compiler output of rmw atomics from gcc and noticed something odd - on Aarch64, rmw operations such as fetch_add can be partially reordered with relaxed loads. On Aarch64, the...

I am working on my demo project - its simple bank. I have one problem. I need to add some virtual money into my account. But I need to do it "like atomic operation", I need to query some ...

What do atomic and nonatomic mean in property declarations? @property(nonatomic, retain) UITextField *userName; @property(atomic, retain) UITextField *userName; @property(retain) UITextField *user...

The following is a quote from C++ Standard - Memory Order: If an atomic store in thread A is tagged memory_order_release and an atomic load in thread B from the same variable is tagged memory_orde...

Which spinlock method is better (in terms of efficiency)? #include <atomic> #define METHOD 1 int main( ) { std::atomic_flag lock { }; #if METHOD == 1 while ( lock.test_and_set( std::mem...

I am currently working a project where I have a large text file (15+ GB) and I'm trying to run a function on each line of the file. In order to speed the task along, I am creating 4 threads and att...

I have linking errors, when trying to do an atomic load of a 16 byte block. I have the following code: #include <atomic> struct MyStruct{ long x; long y; }; struct X{ std::atomic<MySt...

I just found out about the libcu++ library and am trying to use the cuda::atomic variables. I wrote the following program but it is giving me unexpected results: #include <atomic> #include &l...

I am trying to implement a simple counter using SQLite provided with Python. I am using CGI to write simple dynamic web pages. It's the only simple way I can think of to implement a counter. The pr...

Is there a way to set, clear, test and flip a single bit as an atomic operation in c++? For example bitwise variants to "compare_and_swap".

How do atomic operations work, under the hood? Are atomic operations so-called "wait-free"? I'm seeking for a description of the "least common divisor" of atomic operations. What do all atomic op...

I'd like to perform an atomic GET in Redis, and if the value returned is equal to some expected value, I'd like to do a SET, but I want to chain all of this together as one atomic operation. (I'm t...

If you compile code such as #include <atomic> int load(std::atomic<int> *p) { return p->load(std::memory_order_acquire) + p->load(std::memory_order_acquire); } you see that MSV...

While reading the source codes of Go, I have a question about the code in src/sync/once.go: func (o *Once) Do(f func()) { // Note: Here is an incorrect implementation of Do: // // if atomic.Comp...

Is assigning a pointer atomic in Go? Do I need to assign a pointer in a lock? Suppose I just want to assign the pointer to nil, and would like other threads to be able to see it. I know in Java we ...