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Implementing Simple Futures with Coroutines

February 22, 2021

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Instead of return, a coroutine uses co_return returning its result. In this post, I want to implement…

TimelineCpp20

Synchronized Output Streams with C++20

February 18, 2021

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What happens when you write without synchronization to std::cout? You get a mess. With C++20, this should…

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The Five (Seven) Winners of my C++20 book are:

February 16, 2021

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Last week, I launched a quiz. The price was it to win one of the five vouchers for my book "C++20". The…

TimelineCpp20

An Improved Thread with C++20

February 12, 2021

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std::jthread stands for joining thread. In addition to std::thread (C++11), std::jthread automatically…

Undo

Resolving C/C++ Concurrency Bugs More Efficiently with Time Travel Debugging

February 10, 2021

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I'm happy to announce a guest post about Time Travel Debugging with UDB. At the end of the post, I…

TimelineCpp20Interruption

Cooperative Interruption of a Thread in C++20

February 4, 2021

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A typical question in my C++ seminars is: Can a thread be killed? Before C++20, my answer is no. With…

TimelineCpp20

Barriers and Atomic Smart Pointers in C++20

January 29, 2021

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In my last post, I introduced latches in C++20. A latch enables its threads to wait until a counter becomes…

TimelineCpp20

Latches in C++20

January 18, 2021

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Latches and barriers are coordination types that enable some threads to wait until a counter becomes…

TimelineCpp20

Semaphores in C++20

January 14, 2021

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Semaphores are a synchronization mechanism used to control concurrent access to a shared resource. They…

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And the Winners are:

January 11, 2021

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Last week, I launched a quiz. The price was it to win one of the five vouchers for the book "The…

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Five Vouchers to win for my book “C++20”

January 2, 2021

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I give away five vouchers for my book "C++20". In return, I have a question about the Big Four: concepts,…

TimelineCpp20CoreLanguage

Performance Comparison of Condition Variables and Atomics in C++20

December 19, 2020

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After the introduction to std::atomic_flag in my last post, Synchronization with Atomics in C++20, I…

Latest news

Data-Parallel Types – A First ExampleJune 25, 2025 - 4:01 pm
After providing a theoretical introduction to the new C++ 26 feature in my last article, “Data-Parallel Types (SIMD),” I would like to follow up today with a practical example. The following introductory example is from the experimental implementation of the SIMD library. This functionality has been fully adopted in the C++ 26 draft under the […]
Data-Parallel Types (SIMD)June 16, 2025 - 10:24 am
The data-parallel types (SIMD) library provides data-parallel types and operations on them. Today, I want to take a closer look at this. Before diving into the new library, I would like to take a moment to discuss SIMD. SIMD Vectorization refers to the SIMD (Single Instruction, Multiple Data) extensions of a modern processor’s instruction set. […]
Read-copy-update (RCU)June 2, 2025 - 9:54 am
Read-copy-update is strong in multithreading environments where a data structure is read almost exclusively but rarely written. First of all, what is RCU? The excellent Wikipedia page on Read-copy-update provides a good introduction: In computer science, read-copy-update (RCU) is a synchronization mechanism that avoids the use of lock primitives while multiple threads concurrently read and […]
atomic<shared_ptr<>> by Oliver SchädlichMay 19, 2025 - 9:11 am
This blog article is an experiment. A few days ago, I received the following email (translated from German) from Oliver Schädlich (oliver.schaedlich@gmail.com). If, as I hope, this article sparks a discussion, I will be happy to summarize it in my last article. Please send an email to: Rainer.Grimm@ModernesCpp.de. I just read your latest article on […]
Hazard Pointers in C++26May 5, 2025 - 11:12 am
Hazard pointers provide garbage collection in C++ and solve the ABA problem. First of all. What is a hazard pointer? Proposal P2530R3 gives a nice explanation: A hazard pointer is a single-writer multi-reader pointer that can be owned by at most one thread at any time. Only the owner of the hazard pointer can set […]
A Lock-Free Stack: A Hazard Pointer Implementation Explained IIApril 7, 2025 - 11:11 am
In my last post, I started to explain a hazard pointer implementation: A Lock-Free Stack: A Hazard Pointer Implementation Explained I. Today, I will continue to explain the implementation. The Retire List The retire list has the public member functions isInUse, addNode, and deleteUnusedNodes. Additionally, it has the inner class RetireNode, an atomic member of […]