{"id":7550,"date":"2026-07-31T22:56:49","date_gmt":"2026-07-31T14:56:49","guid":{"rendered":"https:\/\/i007.cc\/wordpress\/?p=7550"},"modified":"2026-07-31T22:56:49","modified_gmt":"2026-07-31T14:56:49","slug":"%e8%b0%88%e8%b0%88-lock-free-queue-%e5%a6%82%e4%bd%95%e5%ae%9e%e7%8e%b0%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/i007.cc\/wordpress\/archives\/7550","title":{"rendered":"\u8c08\u8c08 lock-free queue \u5982\u4f55\u5b9e\u73b0\uff1f"},"content":{"rendered":"
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Lock-free \u7f16\u7a0b\u662f C++ \u5e76\u53d1\u91cc\u6700\u96be\u7684\u9886\u57df\uff0cNVIDIA \u9762\u8bd5\u4f1a\u6df1\u6316\u8fd9\u5757\u3002\u4ece\u539f\u7406\u5230\u5b9e\u73b0\u7cfb\u7edf\u8bb2\u4e00\u904d\u3002<\/p>\n

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\u4e3a\u4ec0\u4e48\u9700\u8981 Lock-Free<\/h3>\n

Mutex \u7684\u51e0\u4e2a\u6838\u5fc3\u95ee\u9898\uff1a<\/p>\n

\u4f18\u5148\u7ea7\u53cd\u8f6c<\/strong>\uff1a\u4f4e\u4f18\u5148\u7ea7\u7ebf\u7a0b\u6301\u6709\u9501\uff0c\u9ad8\u4f18\u5148\u7ea7\u7ebf\u7a0b\u88ab\u8feb\u7b49\u5f85\uff0c\u5b9e\u65f6\u7cfb\u7edf\uff08\u6e38\u620f tick\u3001\u97f3\u9891\u7ebf\u7a0b\uff09\u65e0\u6cd5\u63a5\u53d7\u3002<\/p>\n

Convoying\uff08\u62a4\u9001\u6548\u5e94\uff09<\/strong>\uff1a\u4e00\u4e2a\u7ebf\u7a0b\u6301\u9501\u6162\uff0c\u6240\u6709\u7ade\u4e89\u7ebf\u7a0b\u90fd\u5728 OS \u961f\u5217\u91cc\u6392\u961f\uff0c\u541e\u5410\u91cf\u5d29\u6e83\u3002<\/p>\n

Cache line \u4e52\u4e53<\/strong>\uff1amutex \u5185\u90e8\u7684\u72b6\u6001\u5b57\u8282\u88ab\u591a\u4e2a\u6838\u53cd\u590d\u4e89\u593a\uff0ccache \u4e00\u81f4\u6027\u534f\u8bae\u4ea7\u751f\u5927\u91cf\u603b\u7ebf\u6d41\u91cf\u3002<\/p>\n

Lock-free \u7684\u5b9a\u4e49\uff1a\u7cfb\u7edf\u6574\u4f53\u603b\u6709\u7ebf\u7a0b\u5728\u63a8\u8fdb<\/strong>\uff0c\u5355\u4e2a\u7ebf\u7a0b\u53ef\u80fd\u91cd\u8bd5\uff0c\u4f46\u4e0d\u4f1a\u6709\u7ebf\u7a0b\u88ab\u6c38\u4e45\u963b\u585e\u3002<\/p>\n

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\u6838\u5fc3\u539f\u8bed\uff1aCAS \u4e0e Memory Order<\/h3>\n

\u6240\u6709 lock-free \u7ed3\u6784\u90fd\u5efa\u7acb\u5728\u00a0Compare-And-Swap<\/strong>\u00a0\u4e0a\uff1a<\/p>\n

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cpp<\/div>\n
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\/\/ \u4f2a\u8bed\u4e49\uff08CPU \u4fdd\u8bc1\u8fd9\u662f\u539f\u5b50\u64cd\u4f5c\uff09\r\nbool CAS(T* addr, T expected, T desired) {\r\n    if (*addr == expected) {\r\n        *addr = desired;\r\n        return true;\r\n    }\r\n    return false;\r\n}\r\n\r\n\/\/ C++ \u4e2d\r\nstd::atomic<int*> ptr;\r\nint* expected = old_ptr;\r\n\/\/ weak \u7248\u672c\uff1a\u5141\u8bb8\u5076\u53d1\u6027\u5931\u8d25\uff08spurious failure\uff09\uff0c\u7528\u5728\u5faa\u73af\u91cc\u6027\u80fd\u66f4\u597d\r\nptr.compare_exchange_weak(expected, new_ptr,\r\n    std::memory_order_release,   \/\/ \u6210\u529f\u65f6\u7684 ordering\r\n    std::memory_order_relaxed);  \/\/ \u5931\u8d25\u65f6\u7684 ordering<\/pre>\n
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Memory Order \u901f\u67e5<\/strong>\uff08\u8fd9\u662f\u9762\u8bd5\u5fc5\u8003\u70b9\uff09\uff1a<\/p>\n
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relaxed  \u2014 \u53ea\u4fdd\u8bc1\u539f\u5b50\u6027\uff0c\u4e0d\u4fdd\u8bc1\u987a\u5e8f\u3002\u7528\u4e8e\u8ba1\u6570\u5668\u3001\u4e0d\u9700\u8981\u540c\u6b65\u7684\u8bfb\r\nacquire  \u2014 \u6b64\u64cd\u4f5c\u4e4b\u540e\u7684\u8bfb\u5199\u4e0d\u80fd\u88ab\u91cd\u6392\u5230\u6b64\u4e4b\u524d\u3002\u7528\u4e8e\"\u8bfb\u9501\"\r\nrelease  \u2014 \u6b64\u64cd\u4f5c\u4e4b\u524d\u7684\u8bfb\u5199\u4e0d\u80fd\u88ab\u91cd\u6392\u5230\u6b64\u4e4b\u540e\u3002\u7528\u4e8e\"\u5199\u9501\"\r\nseq_cst  \u2014 \u5168\u5c40\u987a\u5e8f\u4e00\u81f4\uff0c\u6700\u5b89\u5168\u4f46\u6700\u6162\uff0c\u662f\u9ed8\u8ba4\u503c\r\n\r\n\u7ecf\u5178\u914d\u5bf9\uff1aproducer \u7528 release \u5199\uff0cconsumer \u7528 acquire \u8bfb<\/pre>\n
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\u7b2c\u4e00\u6b65\uff1aSPSC Queue\uff08\u6700\u5b9e\u7528\uff09<\/h3>\n
\u5355\u751f\u4ea7\u8005\u5355\u6d88\u8d39\u8005\u961f\u5217\uff0c\u6e38\u620f\u5f15\u64ce\u91cc\u6700\u5e38\u89c1\uff1a\u97f3\u9891\u7ebf\u7a0b\u4e0e\u6e38\u620f\u7ebf\u7a0b\u901a\u4fe1\u3001\u6e32\u67d3\u547d\u4ee4\u7f13\u51b2\u533a\u3002SPSC \u4e0d\u9700\u8981 CAS\uff0c\u53ea\u7528 acquire\/release \u5c31\u591f\u4e86\u3002<\/p>\n
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cpp<\/div>\n
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template<typename T, size_t N>\r\nclass SPSCQueue {\r\n    \/\/ N \u5fc5\u987b\u662f 2 \u7684\u5e42\uff0c\u7528\u4f4d\u8fd0\u7b97\u4ee3\u66ff\u53d6\u6a21\r\n    static_assert((N & (N - 1)) == 0, \"N must be power of 2\");\r\n    static constexpr size_t MASK = N - 1;\r\n\r\n    \/\/ \u5173\u952e\uff1ahead \u548c tail \u5fc5\u987b\u5728\u4e0d\u540c cache line\uff01\r\n    \/\/ \u5426\u5219 producer \u548c consumer \u4f1a\u53cd\u590d\u4e89\u593a\u540c\u4e00 cache line\uff08false sharing\uff09\r\n    alignas(64) std::atomic<size_t> head_{0};  \/\/ consumer \u66f4\u65b0\r\n    alignas(64) std::atomic<size_t> tail_{0};  \/\/ producer \u66f4\u65b0\r\n    T buffer_[N];\r\n\r\npublic:\r\n    \/\/ Producer \u8c03\u7528\uff08\u53ea\u6709\u4e00\u4e2a\u7ebf\u7a0b\u8c03\u7528\uff09\r\n    bool push(const T& item) {\r\n        size_t tail = tail_.load(std::memory_order_relaxed);  \/\/ \u8bfb\u81ea\u5df1\u7684 tail\uff0crelaxed \u591f\u4e86\r\n        size_t next = (tail + 1) & MASK;\r\n\r\n        \/\/ \u68c0\u67e5\u961f\u5217\u662f\u5426\u6ee1\uff1a\u9700\u8981\u770b consumer \u7684 head\uff0c\u7528 acquire \u540c\u6b65\r\n        if (next == head_.load(std::memory_order_acquire))\r\n            return false;  \/\/ full\r\n\r\n        buffer_[tail] = item;\r\n\r\n        \/\/ \u53d1\u5e03 tail\uff0c\u7528 release\uff1a\u4fdd\u8bc1\u4e0a\u9762\u7684\u5199\u5165\u5bf9 consumer \u53ef\u89c1\r\n        tail_.store(next, std::memory_order_release);\r\n        return true;\r\n    }\r\n\r\n    \/\/ Consumer \u8c03\u7528\uff08\u53ea\u6709\u4e00\u4e2a\u7ebf\u7a0b\u8c03\u7528\uff09\r\n    bool pop(T& item) {\r\n        size_t head = head_.load(std::memory_order_relaxed);  \/\/ \u8bfb\u81ea\u5df1\u7684 head\r\n\r\n        \/\/ \u68c0\u67e5\u961f\u5217\u662f\u5426\u7a7a\uff1a\u9700\u8981\u770b producer \u7684 tail\uff0c\u7528 acquire \u540c\u6b65\r\n        if (head == tail_.load(std::memory_order_acquire))\r\n            return false;  \/\/ empty\r\n\r\n        item = buffer_[head];\r\n\r\n        \/\/ \u53d1\u5e03 head\uff0c\u7528 release\uff1a\u8ba9 producer \u77e5\u9053\u8fd9\u4e2a\u69fd\u4f4d\u5df2\u7ecf\u88ab\u6d88\u8d39\r\n        head_.store((head + 1) & MASK, std::memory_order_release);\r\n        return true;\r\n    }\r\n\r\n    size_t size() const {\r\n        size_t tail = tail_.load(std::memory_order_acquire);\r\n        size_t head = head_.load(std::memory_order_acquire);\r\n        return (tail - head + N) & MASK;\r\n    }\r\n};\r\n\r\n\/\/ \u4f7f\u7528\u793a\u4f8b\uff1a\u97f3\u9891\u7ebf\u7a0b \u2194 \u6e38\u620f\u7ebf\u7a0b\r\nSPSCQueue<AudioCommand, 1024> audio_queue;\r\n\r\n\/\/ \u6e38\u620f\u7ebf\u7a0b\uff08producer\uff09\r\naudio_queue.push(AudioCommand{.type = PLAY, .sound_id = 42});\r\n\r\n\/\/ \u97f3\u9891\u7ebf\u7a0b\uff08consumer\uff09\r\nAudioCommand cmd;\r\nif (audio_queue.pop(cmd)) {\r\n    play_sound(cmd.sound_id);\r\n}<\/pre>\n
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\u7b2c\u4e8c\u6b65\uff1aMichael-Scott Queue\uff08MPMC \u7ecf\u5178\u7b97\u6cd5\uff09<\/h3>\n
\u591a\u751f\u4ea7\u8005\u591a\u6d88\u8d39\u8005\uff0c1996 \u5e74\u8bba\u6587\uff0c\u662f\u7edd\u5927\u591a\u6570\u65e0\u9501\u961f\u5217\u7684\u57fa\u7840\u3002\u7528\u5e26\u54e8\u5175\u8282\u70b9\u7684\u94fe\u8868\uff0cCAS \u7ade\u4e89\u961f\u5c3e\/\u961f\u5934\u3002<\/p>\n
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cpp<\/div>\n
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template<typename T>\r\nclass MSQueue {\r\n    struct Node {\r\n        T                  data;\r\n        std::atomic<Node*> next{nullptr};\r\n        Node() = default;\r\n        explicit Node(T val) : data(std::move(val)) {}\r\n    };\r\n\r\n    alignas(64) std::atomic<Node*> head_;  \/\/ \u6307\u5411\u54e8\u5175\u8282\u70b9\r\n    alignas(64) std::atomic<Node*> tail_;  \/\/ \u6307\u5411\u6700\u540e\u4e00\u4e2a\u8282\u70b9\r\n\r\npublic:\r\n    MSQueue() {\r\n        Node* dummy = new Node();   \/\/ \u54e8\u5175\u8282\u70b9\uff1ahead \u6c38\u8fdc\u6307\u5411\u4e00\u4e2a\u5df2\u6d88\u8d39\/\u7a7a\u8282\u70b9\r\n        head_.store(dummy, std::memory_order_relaxed);\r\n        tail_.store(dummy, std::memory_order_relaxed);\r\n    }\r\n\r\n    void push(T val) {\r\n        Node* node = new Node(std::move(val));\r\n\r\n        while (true) {\r\n            Node* tail = tail_.load(std::memory_order_acquire);\r\n            Node* next = tail->next.load(std::memory_order_acquire);\r\n\r\n            \/\/ \u4e8c\u6b21\u786e\u8ba4 tail \u6ca1\u53d8\uff08\u5176\u4ed6\u7ebf\u7a0b\u53ef\u80fd\u63a8\u8fdb\u4e86 tail\uff09\r\n            if (tail != tail_.load(std::memory_order_acquire)) continue;\r\n\r\n            if (next == nullptr) {\r\n                \/\/ tail \u786e\u5b9e\u662f\u6700\u540e\u4e00\u4e2a\u8282\u70b9\uff0c\u5c1d\u8bd5\u628a\u65b0\u8282\u70b9\u63a5\u4e0a\u53bb\r\n                if (tail->next.compare_exchange_weak(\r\n                        next, node,\r\n                        std::memory_order_release,\r\n                        std::memory_order_relaxed)) {\r\n                    \/\/ \u63a5\u6210\u529f\u4e86\uff0c\u5c1d\u8bd5\u63a8\u8fdb tail\uff08\u5931\u8d25\u4e5f\u6ca1\u5173\u7cfb\uff0c\u4e0b\u4e2a push \u4f1a\u5e2e\u5fd9\uff09\r\n                    tail_.compare_exchange_weak(\r\n                        tail, node,\r\n                        std::memory_order_release,\r\n                        std::memory_order_relaxed);\r\n                    return;\r\n                }\r\n            } else {\r\n                \/\/ tail \u843d\u540e\u4e86\uff08\u53e6\u4e00\u4e2a\u7ebf\u7a0b\u5df2\u7ecf\u63d2\u5165\u8282\u70b9\u4f46\u8fd8\u6ca1\u63a8\u8fdb tail\uff09\r\n                \/\/ \u5e2e\u5b83\u63a8\u8fdb tail\uff0c\u518d\u91cd\u8bd5\r\n                tail_.compare_exchange_weak(\r\n                    tail, next,\r\n                    std::memory_order_release,\r\n                    std::memory_order_relaxed);\r\n            }\r\n        }\r\n    }\r\n\r\n    bool pop(T& val) {\r\n        while (true) {\r\n            Node* head = head_.load(std::memory_order_acquire);\r\n            Node* tail = tail_.load(std::memory_order_acquire);\r\n            Node* next = head->next.load(std::memory_order_acquire);\r\n\r\n            if (head != head_.load(std::memory_order_acquire)) continue;\r\n\r\n            if (head == tail) {\r\n                if (next == nullptr) return false;  \/\/ \u771f\u7684\u7a7a\u4e86\r\n                \/\/ tail \u843d\u540e\u4e86\uff0c\u5e2e\u5b83\u63a8\u8fdb\r\n                tail_.compare_exchange_weak(tail, next,\r\n                    std::memory_order_release, std::memory_order_relaxed);\r\n            } else {\r\n                \/\/ \u8bfb\u6570\u636e\uff08\u5728 CAS \u4e4b\u524d\uff01CAS \u6210\u529f\u540e head \u53ef\u80fd\u88ab\u522b\u4eba delete\uff09\r\n                val = next->data;\r\n                if (head_.compare_exchange_weak(head, next,\r\n                        std::memory_order_release,\r\n                        std::memory_order_relaxed)) {\r\n                    delete head;  \/\/ \u2190 \u8fd9\u91cc\u6709 ABA \u95ee\u9898\uff01\u4e0b\u9762\u4e13\u95e8\u8bb2\r\n                    return true;\r\n                }\r\n            }\r\n        }\r\n    }\r\n};<\/pre>\n
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ABA \u95ee\u9898\uff1aLock-Free \u6700\u5927\u7684\u5751<\/h3>\n
\u8fd9\u662f\u9762\u8bd5\u6700\u9ad8\u9891\u7684\u8ffd\u95ee\uff0c\u5fc5\u987b\u8bf4\u6e05\u695a\u3002<\/p>\n
\u573a\u666f\uff1a<\/strong><\/p>\n
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\u521d\u59cb\u72b6\u6001\uff1ahead \u2192 A \u2192 B \u2192 C\r\n\r\n\u7ebf\u7a0b 1\uff1a\u8bfb\u5230 head = A\uff0c\u51c6\u5907 CAS(head, A, B)\uff0c\u88ab\u6302\u8d77\r\n\r\n\u7ebf\u7a0b 2\uff1apop A\uff0cpop B\uff0cpush A\uff08\u5185\u5b58\u5206\u914d\u5668\u590d\u7528\u4e86 A \u7684\u5730\u5740\uff09\r\n\u73b0\u5728\uff1ahead \u2192 A' \u2192 C \uff08A' \u548c A \u5730\u5740\u4e00\u6837\uff0c\u4f46\u5185\u5bb9\u53d8\u4e86\uff09\r\n\r\n\u7ebf\u7a0b 1 \u6062\u590d\uff1aCAS(head, A, B)\r\nA \u7684\u5730\u5740\u6ca1\u53d8\uff0cCAS \u6210\u529f\uff01\r\n\u4f46 B \u5df2\u7ecf\u4e0d\u5728\u961f\u5217\u91cc\u4e86\uff0chead \u6307\u5411\u4e86\u4e00\u4e2a\u91ce\u6307\u9488<\/pre>\n
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\u89e3\u6cd5\u4e00\uff1a\u5e26\u6807\u8bb0\u7684\u6307\u9488\uff08Tagged Pointer\uff09<\/strong><\/p>\n
\u5229\u7528\u6307\u9488\u5bf9\u9f50\u540e\u4f4e\u4f4d\u6052\u4e3a 0 \u7684\u7279\u6027\uff0c\u585e\u4e00\u4e2a\u7248\u672c\u53f7\uff1a<\/p>\n
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struct TaggedPtr {\r\n    Node*    ptr;\r\n    uint64_t tag;   \/\/ \u6bcf\u6b21 CAS \u6210\u529f\u5c31 +1\r\n};\r\n\r\n\/\/ \u7528 128-bit CAS\uff08x86 \u4e0a\u662f CMPXCHG16B\uff09\r\nstd::atomic<TaggedPtr> head_;\r\n\r\n\/\/ A \u88ab\u590d\u7528\u65f6\uff0ctag \u5df2\u7ecf\u662f 2 \u4e86\uff0c\u4e0d\u7b49\u4e8e\u7ebf\u7a0b 1 \u4fdd\u5b58\u7684 tag=0\r\n\/\/ CAS \u5931\u8d25\uff0c\u91cd\u8bd5<\/pre>\n
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\u89e3\u6cd5\u4e8c\uff1aHazard Pointer\uff08\u5de5\u4e1a\u7ea7\u65b9\u6848\uff09<\/strong><\/p>\n
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cpp<\/div>\n
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\/\/ \u6bcf\u4e2a\u7ebf\u7a0b\u58f0\u660e\"\u6211\u6b63\u5728\u8bbf\u95ee\u8fd9\u4e2a\u6307\u9488\uff0c\u4e0d\u8981\u91ca\u653e\u5b83\"\r\nthread_local Node* hazard_ptr = nullptr;\r\n\r\nbool pop(T& val) {\r\n    while (true) {\r\n        Node* head = head_.load(std::memory_order_acquire);\r\n        hazard_ptr = head;  \/\/ \u58f0\u660e\u4fdd\u62a4\r\n\r\n        \/\/ \u518d\u6b21\u786e\u8ba4 head \u6ca1\u53d8\uff08\u58f0\u660e\u4fdd\u62a4\u4e4b\u540e\u518d\u9a8c\u8bc1\uff09\r\n        if (head != head_.load(std::memory_order_acquire)) continue;\r\n\r\n        \/\/ ... \u6267\u884c pop \u903b\u8f91 ...\r\n\r\n        if (head_.compare_exchange_weak(...)) {\r\n            hazard_ptr = nullptr;\r\n            \/\/ \u4e0d\u7acb\u523b delete\uff0c\u5148\u653e\u5165\"\u9000\u4f11\u5217\u8868\"\r\n            \/\/ \u626b\u63cf\u6240\u6709\u7ebf\u7a0b\u7684 hazard_ptr\uff0c\u786e\u8ba4\u6ca1\u4eba\u6301\u6709\u518d\u91ca\u653e\r\n            retire(head);\r\n            return true;\r\n        }\r\n    }\r\n}<\/pre>\n
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\u89e3\u6cd5\u4e09\uff1aEpoch-Based Reclamation\uff08\u6700\u5e38\u7528\u4e8e\u6e38\u620f\/\u9ad8\u6027\u80fd\u573a\u666f\uff09<\/strong><\/p>\n
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\u5168\u5c40 epoch\uff1a0 \/ 1 \/ 2 \u8f6e\u8f6c\r\n\u7ebf\u7a0b\u8fdb\u5165\u4e34\u754c\u533a\uff1a\u8bb0\u5f55\u5f53\u524d epoch\r\n\u9000\u51fa\u4e34\u754c\u533a\uff1a\u6e05\u9664\u8bb0\u5f55\r\n\u56de\u6536\u5185\u5b58\uff1a\u786e\u8ba4\u6240\u6709\u7ebf\u7a0b\u90fd\u79bb\u5f00\u4e86\u67d0\u4e2a epoch \u4e4b\u540e\uff0c\u6279\u91cf\u91ca\u653e<\/pre>\n
 <\/p>\n<\/div>\n<\/div>\n
\u8fd9\u662f folly\uff08Facebook\uff09\u3001jemalloc \u7b49\u5e93\u7684\u5b9e\u9645\u505a\u6cd5\uff0c\u5f00\u9500\u6700\u4f4e\u3002<\/p>\n
\n
False Sharing\uff1a\u5bb9\u6613\u5ffd\u89c6\u7684\u6027\u80fd\u6740\u624b<\/h3>\n
\n
\n
<\/div>\n<\/div>\n
cpp<\/div>\n
\n
\/\/ \u9519\u8bef\uff1ahead \u548c tail \u5728\u540c\u4e00 cache line\uff08\u901a\u5e38 64 \u5b57\u8282\uff09\r\nstruct BadQueue {\r\n    std::atomic<size_t> head;   \/\/ consumer \u5199\r\n    std::atomic<size_t> tail;   \/\/ producer \u5199\r\n    \/\/ \u4e24\u4e2a\u6838\u5404\u81ea\u9891\u7e41\u5199\u8fd9\u4e24\u4e2a\u53d8\u91cf\r\n    \/\/ cache \u4e00\u81f4\u6027\u534f\u8bae\u8ba9\u8fd9\u4e2a cache line \u5728\u4e24\u4e2a\u6838\u4e4b\u95f4\u4e0d\u65ad bounce\r\n    \/\/ \u6027\u80fd\u6bd4\u52a0\u9501\u8fd8\u5dee\uff01\r\n};\r\n\r\n\/\/ \u6b63\u786e\uff1a\u5f3a\u5236\u5bf9\u9f50\u5230\u4e0d\u540c cache line\r\nstruct GoodQueue {\r\n    alignas(64) std::atomic<size_t> head;\r\n    alignas(64) std::atomic<size_t> tail;\r\n};<\/pre>\n
 <\/p>\n<\/div>\n<\/div>\n
\u5b9e\u6d4b\u6570\u636e\uff1a\u5728\u9ad8\u7ade\u4e89\u573a\u666f\u4e0b\uff0c\u52a0\u00a0alignas(64)<\/code>\u00a0\u53ef\u4ee5\u8ba9\u541e\u5410\u91cf\u63d0\u5347 3-5 \u500d\u3002<\/p>\n
\n
\u6e38\u620f\u91cc\u7684\u5b9e\u9645\u5e94\u7528<\/h3>\n
\n\n\n\n\n\n\n\n\n\n
\u573a\u666f<\/th>\n\u961f\u5217\u7c7b\u578b<\/th>\n\u539f\u56e0<\/th>\n<\/tr>\n<\/thead>\n
\u97f3\u9891\u547d\u4ee4\uff08\u6e38\u620f\u7ebf\u7a0b \u2192 \u97f3\u9891\u7ebf\u7a0b\uff09<\/td>\nSPSC Ring Buffer<\/td>\n\u5355\u751f\u4ea7\u8005\u5355\u6d88\u8d39\u8005\uff0c\u6700\u5feb<\/td>\n<\/tr>\n
Job System \u4efb\u52a1\u63d0\u4ea4<\/td>\nMPMC<\/td>\n\u591a\u4e2a\u7ebf\u7a0b\u63d0\u4ea4\u4efb\u52a1<\/td>\n<\/tr>\n
Work Stealing\uff08Naughty Dog \u7684 Fiber \u7cfb\u7edf\uff09<\/td>\n\u6bcf\u7ebf\u7a0b\u4e00\u4e2a SPSC + \u5077\u53d6\u7528 MPSC<\/td>\n\u5c40\u90e8\u6027\u597d + \u8d1f\u8f7d\u5747\u8861<\/td>\n<\/tr>\n
\u7f51\u7edc\u5305\u63a5\u6536\u961f\u5217<\/td>\nMPSC\uff08\u591a IO \u7ebf\u7a0b \u2192 \u5355\u903b\u8f91\u7ebf\u7a0b\uff09<\/td>\n\u591a\u7f51\u5361 IO \u7ebf\u7a0b\u5e76\u53d1\u5199<\/td>\n<\/tr>\n
\u6e32\u67d3\u547d\u4ee4\u7f13\u51b2<\/td>\nSPSC<\/td>\n\u6e38\u620f\u7ebf\u7a0b\u751f\u4ea7\uff0c\u6e32\u67d3\u7ebf\u7a0b\u6d88\u8d39<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
\n
\u9762\u8bd5\u65f6\u7684\u7b54\u9898\u601d\u8def<\/h3>\n
NVIDIA \u9762\u8bd5\u5b98\u95ee\u8fd9\u9053\u9898\uff0c\u5b9e\u9645\u5728\u8003\u4e09\u4ef6\u4e8b\uff1a\u4f60\u77e5\u4e0d\u77e5\u9053 CAS \u548c memory order \u7684\u914d\u5408\uff1b\u4f60\u6709\u6ca1\u6709\u8e29\u8fc7\u6216\u8005\u7406\u89e3 ABA \u95ee\u9898\uff1b\u4f60\u77e5\u4e0d\u77e5\u9053 false sharing \u8fd9\u4e2a\u9690\u5f62\u6027\u80fd\u6740\u624b\u3002<\/p>\n
\u56de\u7b54\u5efa\u8bae\uff1a\u5148\u8bf4 SPSC\uff08\u6700\u7b80\u5355\u3001\u6700\u5b9e\u7528\uff0c\u914d\u5408 acquire\/release \u89e3\u91ca memory order\uff09\uff1b\u518d\u8bf4 MS Queue\uff08CAS \u7ade\u4e89\u673a\u5236\uff09\uff1b\u7136\u540e\u4e3b\u52a8\u63d0 ABA \u95ee\u9898\uff0c\u8bf4\u51fa\u81f3\u5c11\u4e00\u79cd\u89e3\u6cd5\u3002\u6700\u540e\u52a0\u4e00\u53e5\u00a0alignas(64)<\/code>\u00a0\u9632 false sharing\uff0c\u5c55\u793a\u4f60\u771f\u7684\u5199\u8fc7\u8fd9\u7c7b\u4ee3\u7801\u3002<\/p>\n
\u5982\u679c\u88ab\u8ffd\u95ee”\u4f60\u5b9e\u9645\u7528\u8fc7\u54ea\u79cd”\uff0c\u628a\u4f60\u9879\u76ee\u91cc\u7684\u771f\u5b9e\u573a\u666f\u8bf4\u51fa\u6765\uff0c\u6bd4\u6cdb\u6cdb\u63cf\u8ff0\u7b97\u6cd5\u6709\u8bf4\u670d\u529b\u5f97\u591a\u3002<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"
Lock-free \u7f16\u7a0b\u662f C++ \u5e76\u53d1<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"colormag_page_container_layout":"default_layout","colormag_page_sidebar_layout":"default_layout","footnotes":""},"categories":[24],"tags":[],"class_list":["post-7550","post","type-post","status-publish","format-standard","hentry","category-value_docs"],"_links":{"self":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/7550","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/comments?post=7550"}],"version-history":[{"count":0,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/7550\/revisions"}],"wp:attachment":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/media?parent=7550"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/categories?post=7550"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/tags?post=7550"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}