wehub-resource-sync
48 lines
1.5 KiB
C++
Executable File
48 lines
1.5 KiB
C++
Executable File
#pragma once
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#include <deque>
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#include <thread>
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#ifdef NUM_THREAD_WORKERS
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static const size_t kNumThreadWorkers = NUM_THREAD_WORKERS;
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#else
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static const size_t kNumThreadWorkers = std::thread::hardware_concurrency();
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#endif
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// A thread pool that only ensures there are at most N number of active threads in the pool,
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// without any regard to thread creation/destruction overhead.
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// However, if `numWorkers` is set to 0, then there is no limit to the number of active threads.
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class BasicThreadPool {
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public:
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BasicThreadPool(const size_t numWorkers) : kNumWorkers(numWorkers) {}
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BasicThreadPool() : kNumWorkers(kNumThreadWorkers) {}
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~BasicThreadPool() {
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// Ensure all threads are joined before destroying itself
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joinAll();
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}
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bool empty() const { return mThreadPool.empty(); }
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template <class Func, class... Args>
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void push(Func&& func, Args&&... args) {
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// Create a new thread and start executing it
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mThreadPool.emplace_back(std::forward<Func>(func), std::forward<Args>(args)...);
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// Join the threads once the number of active threads have reached `kNumWorkers`.
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// However if `kNumWorkers` is 0, allow unlimited number of active threads.
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if (kNumWorkers && mThreadPool.size() == kNumWorkers)
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joinAll();
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}
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void joinAll() {
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for (auto& thread : mThreadPool)
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thread.join();
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mThreadPool.clear();
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}
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private:
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const size_t kNumWorkers;
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std::deque<std::thread> mThreadPool;
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}; |