SOFTWARE OR THE USE OR OTHER DEALINGS IN THE // SOFTWARE. Lockfree, MPMC Queue - Legal CppCon 2024 | Erez Strauss | Lockfree, MPMC Queue https://github.com/erez-strauss/lockfree_mpmc_queueAbout me ● C++/C com/in/erezstrauss/ 3 CppCon 2024 | Erez Strauss | Lockfree, MPMC Queue https://github.com/erez-strauss/lockfree_mpmc_queueLockfree, MPMC Queue - Agenda 1. Trading Platform, Latency 2. Queues Environment 5. Queues Classification 6. Queue creation, push, pop 7. Queue internals 8. Testing 9. Performance - Benchmarking 4 CppCon 2024 | Erez Strauss | Lockfree, MPMC Queue https://github.com/erez-strau

We need a system Orchestrator to implement the robot behaviorRobot Behaviors This Coordinator or Task Planner is also the highest level of abstraction of our system, where we focus on WHAT the robot

used when we created them.” - Albert EinsteinSo what is there to Rethink?Rethinking: Task Queues Problem #1 - Task Queues Do Not Scale Well: ● Contention: ○ Even the most meticulously designed lock-free problems: ○ Task starvation ○ Load balancing ○ Forfeits strict FIFO behaviour ○ Increases memory footprint (or requires allocations) ○ Terrible task selection “fairness” Task Thread Thread Thread Task Task Task Task Task Task Task Task Back Front Task Queue Execute Task() Thread Thread PoolRethinking: Task Queues Problem #2 - No Inherent Support For Prioritization: ● Priority queues address this but

in a top-down task graph What is Task Graph-based Programming System (TGPS) Code 4• TGPS encapsulates function calls and their dependencies in a top-down task graph What is Task Graph-based Programming top-down task graph What is Task Graph-based Programming System (TGPS) Code A B C D B A C D 6• TGPS encapsulates function calls and their dependencies in a top-down task graph What is Task Graph-based sched; 2 task_a = sched.emplace([](&){ 3 // Code block A; 4 }); 5 task_b = sched.emplace([](&){ 6 // Code block B; 7 }); 8 task_c = sched.emplace([](&){ 9 // Code block C; 10 }); 11 task_d = sched

. . . . . . . . . . . 93 7 Tutorials 95 7.1 Using Celery with Redis/Database as the messaging queue. . . . . . . . . . . . . . . . . . . . . . . 95 7.2 Tutorial: Creating a click counter using carrot 112 9 API Reference 113 9.1 Task Decorators - celery.decorators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 9.2 Defining Tasks - celery.task.base . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 9.3 Task Sets, Subtasks and Callbacks - celery.task.sets . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 9.4 Executing Tasks - celery

com/ask/celery/ Keywords task queue, job queue, asynchronous, rabbitmq, amqp, redis, python, webhooks, queue, dis- tributed – Celery is an open source asynchronous task queue/job queue based on distributed of the task can be stored for later retrieval (called its “tombstone”). 1.1.2 Example You probably want to see some code by now, so here’s an example task adding two numbers: from celery.task import import task @task def add(x, y): return x + y You can execute the task in the background, or wait for it to finish: >>> result = add.delay(4, 4) >>> result.wait() # wait for and return the result 8 Simple

. . . . . . . . . . . 97 7 Tutorials 103 7.1 Using Celery with Redis/Database as the messaging queue. . . . . . . . . . . . . . . . . . . . . . . 103 7.2 Debugging Tasks Remotely (using pdb) . . . . . . . . . . . . . . 192 10.4 celery.task . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192 10.5 celery.task.base . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 10.6 celery.task.sets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201 10.7 celery.result

. . . . . . . . . . 121 7 Tutorials 127 7.1 Using Celery with Redis/Database as the messaging queue. . . . . . . . . . . . . . . . . . . . . . . 127 7.2 Debugging Tasks Remotely (using pdb) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219 10.2 celery.app.task . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222 10 . . . . . . . . . . . 231 10.5 celery.task . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232 10.6 celery.task.base . . . . . . . . . . . . . . . . .

com/ask/celery/ Keywords task queue, job queue, asynchronous, rabbitmq, amqp, redis, python, webhooks, queue, dis- tributed – Celery is an open source asynchronous task queue/job queue based on distributed workload. The result of the task can be stored for later retrieval (called its “tombstone”). 1.1.2 Example You probably want to see some code by now, so here’s an example task adding two numbers: from from celery.decorators import task @task def add(x, y): return x + y You can execute the task in the background, or wait for it to finish: >>> result = add.delay(4, 4) >>> result.wait() # wait for and return

operations with the tools required to maintain such a system. It’s a task queue with focus on real-time processing, while also supporting task scheduling. Celery has a large and diverse community of users and Release 4.1.0 • What’s a Task Queue? • What do I need? • Get Started • Celery is... • Features • Framework Integration • Quick Jump • Installation What’s a Task Queue? Task queues are used as a mechanism to distribute work across threads or machines. A task queue’s input is a unit of work called a task. Dedicated worker processes constantly monitor task queues for new work to perform. Celery communicates