Additional points if this implementation is : Light-weight: glib, APR, NSPR and others come with a big buy-in, I'd rather have just 2 files (header and implementation). If not, it is better to understand it here: … A queue of structs that hold job descriptions is easy to implement. If not, NULL should be passed. You can pass a single argument to the function if you wish. Please note that above is simple example to show how threads work. The thread queue continuously fetches the tasks in the task queue to execute. The center of a thread pool will be how to assign work to the worker threads. Now when a request comes, then it directly goes to the thread pool and checks whether there are any free threads available or not. Will return a new threadpool with 4 threads. thpool_wait(thpool) Will wait for all jobs (both in queue and currently running) to finish. I … Accessing a global variable in a thread is generally a bad idea. Still maintained. Generally speaking, the thread pool has a task queue and a thread queue. Thread Pool in C#: Thread pool in C# is nothing but a collection of threads that can be reused to perform no of tasks in the background. thpool_add_work(thpool, (void*)function_p, (void*)arg_p) Will add new work to the pool. A thread pool may also replace a thread if it dies of an unexpected exception. Threadpool in C++ is basically a pool having a fixed number of threads used when we want to work multiple tasks together (run multiple threads concurrently). I would like to see your review of it. When the task queue is empty, the thread blocks and waits for new tasks to be added. Tested on several platforms (Linux, BSD, Mac OS X, etc.). A thread pool may contain a number of threads each performing a specific task. You can also queue work items that are not related to a wait operation to the thread pool. This thread sits idle in the thread pool when there are no tasks and when a task arrives, it is sent to the thread pool and gets assigned to the thread. It is assumed that the reader has a certain multithreading foundation. What open-source implementation(s) in C for a pthreads thread pool would you recommend ? if all the threads in a thread pool are occupied in performing there task then a new task, which need to be processed wait in a queue until a thread becomes free.net framework provides thread pool through the threadpool class. threadpool-a simple thread pool based on pthread Introduction to Thread Pool Thread pool can be said to be a component that is often used in projects. In computer programming, a thread pool is a software design pattern for achieving concurrency of execution in a computer program. I wrote a simple thread pool, which works pretty well. Often also called a replicated workers or worker-crew model, a thread pool maintains multiple threads waiting for tasks to be allocated for concurrent execution by the supervising program. This method takes as a parameter a reference to the method or delegate that will be called by the thread selected from the thread pool. Usually, thread pools are bound to a queue from which tasks are dequeued for execution by worker threads. You need to protect access of the queue by multiple threads and be able to know when the queue is empty (and pause pool threads) and full (if needed). To request that a work item be handled by a thread in the thread pool, call the QueueUserWorkItem method. Recently, I wrote a thread pool. A thread pool can be tuned for the size of the threads it holds. Work is simply a function. In practice, if it is required to access global variable by multiple threads, then they should be accessed using a mutex. 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