Ongoing Optimization: Sequential Consistency with CppMem
With atomic data types, you can tailor your program to your needs and optimize it. But now we are in the domain of multithreading experts.
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Entries by Rainer Grimm
Ongoing Optimization: Locks and Volatile with CppMem
The easiest way to solve the undefined behaviour in the post Ongoing Optimization: Unsynchronized access is, to use a lock.
Looking for Proofreaders for my New C++ Book
Something completely different. I’m looking for English proofreaders for my new book.
Ongoing Optimization: Unsynchronized Access with CppMem
I described my challenge in the last post. Let’s ‘s start with our process of ongoing optimization. To be sure, I verify my reasoning with CppMem. I once made a big mistake in my presentation at Meeting C++ 2014.
Ongoing Optimization
Now it’s time to put the theory into practice. The job is relatively easy. A small program should undergo ongoing optimization.
CppMem – An Overview
CppMem is an interactive tool for exploring the behavior of small code snippets of the C++ memory model. No, it should have to be in the toolbox of each programmer who deals seriously with the memory model.
Relaxed Semantics
The relaxed semantics is the end of the scale. The relaxed semantic is the weakest of all memory models and guarantees that the operations on atomic variables are atomic.
Acquire-Release Fences
Acquire and release fences guarantee similar synchronization and ordering constraints as atomics with acquire-release semantics. Similar because the differences are in the details.
Fences are Memory Barriers
The key idea of a std::atomic_thread_fence is to establish synchronization and ordering constraints between threads without an atomic operation.
Acquire-Release Semantics – The Typical Misunderstanding
A release operation synchronizes-with an acquire operation on the same atomic variable. So we can easily synchronise threads, if … . Today’s post is about the if.