Archive for category: Multithreading – Memory Model

relaxed

Relaxed Semantics

July 27, 2016

/

The relaxed semantics is the end of the scale. The relaxed semantic is the weakest of all memory models…

acquireOperation

Acquire-Release Fences

July 21, 2016

/

Acquire and release fences guarantee similar synchronization and ordering constraints as atomics with…

FullFence

Fences are Memory Barriers

July 19, 2016

/

The key idea of a std::atomic_thread_fence is to establish synchronization and ordering constraints between…

acquireReleaseWithWaiting

Acquire-Release Semantics – The Typical Misunderstanding

July 16, 2016

/

A release operation synchronizes-with an acquire operation on the same atomic variable. So we can easily…

trans

Transitivity of the Acquire-Release Semantic

July 12, 2016

/

A release operation synchronizes with an acquire operation on the same atomic variable and establishes,…

acquireReleaseConsume

memory_order_consume

July 9, 2016

/

std::memory_order_consume is the most legendary of the six memory models. That's for two reasons. On…

criticalRegion

Acquire-Release Semantic

July 4, 2016

/

With the acquire-release semantics, the memory model gets very thrilling. Because now, we do not have…

producerConsumer

Sequential Consistency applied

July 2, 2016

/

I have introduced In the post Sequential Consistency the default memory model. This model, in which all…

atomicOperationsReadWriteEng

Synchronization and Ordering Constraints

June 28, 2016

/

In this post, our tour through the c++ memory model goes one step deeper. Until now, the posts were only…

Atomics

June 22, 2016

/

In addition to booleans, there is atomics for pointers, integrals, and user-defined types. The rules…

Latest news

std::execution: SenderDecember 16, 2024 - 11:25 am
std::execution offers three types of senders: factories, adapters, and consumers. I’ll take a closer look at these today. Most of the following content is from proposal P2300R10. I will try to represent it more concisely. Sender Factory A sender factory is an algorithm that takes no senders as parameters and returns a sender. execution::schedule execution::sender […]
std::execution: Composition of SendersDecember 9, 2024 - 10:25 am
Most sender adaptors are composable using the pipe operator. Let me start with a simple example of composition with the pipe operator. Instead of the nested function calls call1(call2(input)) you can write call1 | call2(input) or even: input | call1 | call2 Function composition Okay, this example was straightforward. Let’s do something more complicated. Proposal […]
std::execution: Inclusive ScanDecember 2, 2024 - 10:30 am
Inclusive scan solves problems related to range queries, such as calculating the sum of a range of elements in an array. It is also used in range minimum queries and various other algorithms. Before I present the asynchronous inclusive scan, I introduce the inclusive scan, aka prefix sum. Prefix Sum In computer science, the prefix […]
std::execution: Asynchronous AlgorithmsNovember 25, 2024 - 9:06 am
std::execution supports many asynchronous algorithms for various workflows. Presenting proposal P2300R10 is not easy. First, it is very powerful, and second, it is very long. Therefore, I concentrate on specific aspects of the proposal. What are the priorities of this proposal? Priorities The terms execution resource, execution agent, and scheduler are essential for the understanding […]
std::executionNovember 18, 2024 - 9:03 am
std::execution, previously known as executors or Senders/Receivers, provides “a Standard C++ framework for managing asynchronous execution on generic execution resources“. (P2300R10) Side Note Change of plans. My original plan was to present the C++26 library after the core language. However, the implementation status of the library is not good enough. Therefore, I decided to continue […]
C++26 Core Language: Small ImprovementsNovember 4, 2024 - 8:34 am
There are more small improvements in the C++26 language, which you should know. static_assert extension First, here’s the syntax of static_assert in C++11: static_assert(compile time predicate, unevaluated string) With C++26, the string can be a user-defined type having the following properties: static_assert can now be used with a format string. Here’s a nice example from […]