org/z/vqnfvh9WxCppCon 2023 8 David Olsen - Back to Basics: Concurrency STD::COUNTING_SEMAPHORE Lightweight synchronization primitive that can control access to a shared resource Maintains an internal counter Calls Parent thread write Child thread readCppCon 2023 65 David Olsen - Back to Basics: Concurrency SYNCHRONIZATION: THREAD CREATION Creating a thread synchronizes the parent and child threads All memory changes thread write Parent thread readCppCon 2023 69 David Olsen - Back to Basics: Concurrency SYNCHRONIZATION: THREAD JOIN Joining a thread synchronizes the parent and child threads All memory changes

dathskovsky@speedata.io | www.linkedin.com/in/alexdathskovsky Volatile ● Volatile is not a synchronization tool ● Volatile doesn’t affect threading ● It's not an atomic value ● It doesn’t add barriersAlex about itAlex Dathskovsky | alex.dathskovsky@speedata.io | www.linkedin.com/in/alexdathskovsky Synchronization contAlex Dathskovsky | alex.dathskovsky@speedata.io | www.linkedin.com/in/alexdathskovsky Compiler ExampleAlex Dathskovsky | alex.dathskovsky@speedata.io | www.linkedin.com/in/alexdathskovsky Synchronization Tools ● std::mutex, std::conditional_variable ● std::lock_guard – RAII helper for lockingAlex

f.dev@gmail.comOutline • Motivation • Overview • Patterns • Lifetime • Exceptions • RAII • Synchronization • Conclusions Francesco Zoffoli - Coroutine Patterns and How to Use Them - CppCon 2023 4Motivation 2023 16 Queue Thread foo()_1 Executor foo()_2Patterns • Lifetime • Exceptions • RAII • Synchronization Francesco Zoffoli - Coroutine Patterns and How to Use Them - CppCon 2023 17Lifetime Francesco Patterns and How to Use Them - CppCon 2023 62Synchronization Francesco Zoffoli - Coroutine Patterns and How to Use Them - CppCon 2023 63Synchronization Needed? Francesco Zoffoli - Coroutine Patterns

Concurrent Programming §36. Concurrency Synchronization Overview §37. Channel Use Cases §38. How to Gracefully Close Channels §39. Other Concurrency Synchronization Techniques - the sync standard package function calls and panic/recover (§13), and the concurrency synchronization techniques introduced in the later article concurrency synchronization overview (§36) can be viewed as control flow statements in functions in the fmt standard package is very small for this specific program). Concurrency Synchronization Concurrent computations may share resources, generally memory resource. The following are some

About Collaboration 29 Manage Cloud 29 Navicat Cloud 29 On-Prem Server 31 Push Synchronization 33 Cache and Local Copies 34 Projects 34 Work With Projects 34 Manage Members 35 178 Confirm & Start Data Transfer (Step 3) 179 Data Synchronization (Available only in Non-Essentials Edition) 180 About Data Synchronization 180 Choose Connections & Comparing Options (Step 1) Execute Selected Scripts (Step 4) 182 Structure Synchronization (Available only in Non-Essentials Edition) 183 About Structure Synchronization 183 Choose Connections & Comparing Options (Step

About Collaboration 28 Manage Cloud 28 Navicat Cloud 28 On-Prem Server 30 Push Synchronization 32 Cache and Local Copies 33 Projects 33 Work With Projects 33 Manage Members 34 172 Confirm & Start Data Transfer (Step 3) 174 Data Synchronization (Available only in Non-Essentials Edition) 174 About Data Synchronization 174 Choose Connections & Comparing Options (Step 1) Execute Selected Scripts (Step 4) 176 Structure Synchronization (Available only in Non-Essentials Edition) 177 About Structure Synchronization 177 Choose Connections & Comparing Options (Step

About Collaboration 28 Manage Cloud 28 Navicat Cloud 28 On-Prem Server 30 Push Synchronization 32 Cache and Local Copies 33 Projects 33 Work With Projects 33 Manage Members 34 177 Confirm & Start Data Transfer (Step 3) 178 Data Synchronization (Available only in Non-Essentials Edition) 179 About Data Synchronization 179 Choose Connections & Comparing Options (Step 1) Execute Selected Scripts (Step 4) 181 Structure Synchronization (Available only in Non-Essentials Edition) 182 About Structure Synchronization 182 Choose Connections & Comparing Options (Step

Software Architecture (Volume 2 and 4) ▪ Concurrent Programming in JavaConcurrency Patterns Synchronization Patterns Dealing with Sharing ▪ Copied Value ▪ Thread-Specific Storage ▪ Future Dealing Suspension Concurrent Architecture Active Object Monitor Object ReactorConcurrency Patterns Synchronization Patterns Dealing with Sharing ▪ Copied Value ▪ Thread-Specific Storage ▪ Future Dealing }); future.get(); Future: receiver get Promise: sender set channelConcurrency Patterns Synchronization Patterns Dealing with Sharing ▪ Copied Value ▪ Thread-Specific Storage ▪ Future Dealing

forever) – e.g., 1 worker drops out before collective synchronization • Correct handling requires communication – Data movement, or synchronization (same thing) – Stop other workers from waiting forever – Reduce on “did everybody succeed?” – Collect info for recovery and/or reporting • Prevent synchronization-related deadlock – If you must synchronize… – … use it as opportunity to communicate error state Think of parallel loop body as a sequence of “local” blocks, punctuated by synchronization – Always participate in synchronization – Give each block a “bypass”: if error, do nothing harmlessly and pass

allowed to look at the variable x while this thread is modifying it; and without some kind of synchronization, there’s no way to ensure that this thread isn’t modifying it right when you happen to be deadline) printf("A: %d\n", ++counter); threadB.join(); 11 This is a data race. No synchronization exists between these two accesses, and at least one of them is a write. (In fact, both are will produce different outputs. That might be considered a bug, but it’s not UB.)“Logical synchronization” Problem statement: std::thread threadB = std::thread([&](){ waitUntilUnblocked();