![\"\u5c01\u9762\u4fe1\u606f\u56fe\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/10\/20261021203244-6ad9216cf3ae0.webp\")
<\/p>\n<\/p>\n
\u5728\u5e76\u53d1\u7f16\u7a0b\u7684\u53d1\u5c55\u53f2\u4e2d，**\u53cc\u91cd\u68c0\u67e5\u9501\u5b9a\u6a21\u5f0f（Double-Checked Locking Pattern, \u7b80\u79f0 DCLP）**\u662f\u4e00\u5ea7\u88ab\u65e0\u6570\u6280\u672f\u5148\u8d24\u53cd\u590d\u89e3\u5256\u3001\u5374\u4f9d\u7136\u5728\u73b0\u4ee3\u591a\u6838\u670d\u52a1\u5668\u4e0a\u9891\u7e41\u5236\u9020\u7ebf\u4e0a\u5d29\u6e83\u7684\u201c\u7ecf\u5178\u8ff7\u5bab\u201d\u3002<\/p>\n
\u5176\u6700\u521d\u7684\u8bbe\u8ba1\u52a8\u673a\u6781\u5176\u5355\u7eaf\u800c\u4f18\u96c5：\u4e3a\u4e86\u5728\u591a\u7ebf\u7a0b\u73af\u5883\u4e0b\u5b9e\u73b0\u61d2\u52a0\u8f7d（Lazy Initialization）\u5355\u4f8b\u6a21\u5f0f，\u540c\u65f6\u907f\u514d\u6bcf\u6b21\u83b7\u53d6\u5355\u4f8b\u90fd\u7ecf\u5386\u4e92\u65a5\u9501（std::mutex）\u9ad8\u6602\u7684\u52a0\u9501\u89e3\u9501\u5f00\u9500，\u5de5\u7a0b\u5e08\u4eec\u8bbe\u8ba1\u4e86\u201c\u5148\u68c0\u67e5\u6307\u9488\u662f\u5426\u4e3a\u7a7a\u3001\u82e5\u4e3a\u7a7a\u518d\u52a0\u9501\u5e76\u4e8c\u6b21\u68c0\u67e5\u201d\u7684\u53cc\u91cd\u68c0\u6d4b\u7ed3\u6784\u3002<\/p>\n
\u7136\u800c，\u5728 2004 \u5e74 Scott Meyers \u4e0e Andrei Alexandrescu \u5171\u540c\u53d1\u8868\u9707\u64bc\u4e1a\u754c\u7684\u8457\u540d\u8bba\u6587\u4e4b\u524d，\u6574\u4e2a C\/C++ \u5de5\u4e1a\u754c\u751a\u81f3\u672a\u66fe\u610f\u8bc6\u5230：\u57fa\u4e8e\u4f20\u7edf\u88f8\u6307\u9488\u5b9e\u73b0\u7684 DCLP，\u5728\u73b0\u4ee3\u8d85\u6807\u91cf\u591a\u6838\u5904\u7406\u5668\u4e0a\u4ece\u6839\u672c\u4e0a\u5c31\u662f\u5f7b\u5e95\u9519\u8bef\u7684！<\/p>\n
\u5982\u679c\u4e0d\u5f15\u5165\u4e25\u683c\u7684\u73b0\u4ee3 C++ \u5185\u5b58\u6a21\u578b\u5c4f\u969c（Acquire-Release \u8bed\u4e49），\u770b\u4f3c\u5b8c\u7f8e\u7684 DCLP \u4f1a\u5728\u5e76\u53d1\u9ad8\u538b\u4e0b\u77ac\u95f4\u5f15\u53d1\u707e\u96be\u6027\u7684**\u201c\u534a\u521d\u59cb\u5316\u5bf9\u8c61\u9038\u51fa（Half-Initialized Object Escape）\u201d**\u2014\u2014\u5f53\u67d0\u4e2a\u7ebf\u7a0b\u68c0\u6d4b\u5230\u5355\u4f8b\u6307\u9488\u5df2\u7ecf\u975e\u7a7a\u65f6，\u5176\u6240\u6307\u5411\u7684\u5185\u5b58\u7a7a\u95f4\u4e2d\u7684\u6210\u5458\u53d8\u91cf\u53ef\u80fd\u6839\u672c\u8fd8\u6ca1\u6709\u88ab\u5199\u5165，\u4ece\u800c\u5bfc\u81f4\u4e1a\u52a1\u7ebf\u7a0b\u5728\u4e00\u4e2a\u5145\u65a5\u7740\u968f\u673a\u672a\u521d\u59cb\u5316\u5783\u573e\u6570\u636e\u7684\u201c\u534a\u6210\u54c1\u5bf9\u8c61\u201d\u4e0a\u72c2\u5954，\u6700\u7ec8\u5f15\u53d1\u707e\u96be\u6027\u7684\u5185\u5b58\u5d29\u6e83！<\/p>\n
\u672c\u6587\u5c06\u4ece\u7269\u7406\u5fae\u67b6\u6784\u5c42\u9762\u7684\u6307\u4ee4\u91cd\u6392\u4e0e\u5199\u7f13\u51b2\u533a\u6392\u7a7a\u673a\u5236\u5207\u5165，\u5f7b\u5e95\u6495\u5f00 DCLP \u5d29\u6e83\u7684\u672c\u8d28，\u5e76\u7ed9\u51fa\u57fa\u4e8e C++23 \u539f\u5b50\u5185\u5b58\u6a21\u578b\u4e0e\u73b0\u4ee3\u7f16\u8bd1\u671f\u7279\u6027\u7684\u7ec8\u6781\u5de5\u4e1a\u89e3\u6cd5\u3002<\/p>\n
\u8981\u7406\u89e3 DCLP \u4e3a\u4ec0\u4e48\u5fc5\u7136\u5d29\u6e83，\u5fc5\u987b\u6df1\u5165\u6c47\u7f16\u6307\u4ee4\u5c42\u9762，\u5ba1\u89c6\u4ee3\u7801 instance = new Singleton(); \u7a76\u7adf\u5bf9\u5e94\u4e86\u54ea\u4e9b\u7269\u7406\u673a\u5668\u52a8\u4f5c\u3002<\/p>\n
\u5728\u7f16\u8bd1\u5668\u4e0e\u8d85\u6807\u91cf CPU \u89c6\u89d2\u4e0b，\u8fd9\u884c\u4ee3\u7801\u5fc5\u987b\u88ab\u4e25\u683c\u62c6\u89e3\u4e3a\u4e09\u4e2a\u6b65\u9aa4：<\/p>\n
\u4f20\u7edf DCLP \u81f4\u547d\u5d29\u6e83\u65f6\u7a7a\u4ea4\u9519:
\nThread 1 (\u6267\u884c\u521d\u59cb\u5316):
\n Step 1: \u5206\u914d\u5185\u5b58 (\u5f97\u5230\u5730\u5740 0x1000)
\n Step 3: \u8d4b\u503c instance = 0x1000 <—+ (\u707e\u96be！\u7f16\u8bd1\u5668\/CPU \u4e71\u5e8f\u5c06\u53d1\u5e03\u6307\u9488\u91cd\u6392\u5230\u4e86\u524d\u9762！)
\n |
\nThread 2 (\u8c03\u7528 getInstance): |
\n \u5916\u5c42\u68c0\u67e5: if (instance != nullptr) | (\u6b64\u65f6 instance \u5df2\u7ecf\u975e\u7a7a！)
\n \u4ee5\u4e3a\u5df2\u7ecf\u521d\u59cb\u5316\u5b8c\u6bd5，\u76f4\u63a5\u8fd4\u56de 0x1000 |
\n \u5f00\u59cb\u8bbf\u95ee instance->data_ | (\u6b64\u65f6 Step 2 \u6839\u672c\u5c1a\u672a\u6267\u884c！\u8bbf\u95ee\u5230\u672a\u521d\u59cb\u5316\u7684\u968f\u673a\u5185\u5b58\u5783\u573e！)
\n | ===> \u53d1\u751f\u6bb5\u9519\u8bef SIGSEGV \u6216\u903b\u8f91\u4e25\u91cd\u6495\u88c2！
\nThread 1 (\u8fd9\u624d\u5f00\u59cb\u6267\u884c): |
\n Step 2: \u6267\u884c\u5bf9\u8c61\u6784\u9020\u51fd\u6570 ————+ (\u4e3a\u65f6\u5df2\u665a，Thread 2 \u5df2\u7ecf\u96ea\u5d29！)<\/p>\n
\u4e3a\u4ec0\u4e48\u7f16\u8bd1\u5668\u548c CPU \u6562\u4e8e\u5c06\u6b65\u9aa4 3 \u91cd\u6392\u5230\u6b65\u9aa4 2 \u4e4b\u524d？\u6839\u636e C++ \u6807\u51c6\u8457\u540d\u7684\u201cAs-if \u89c4\u5219\u201d，\u5728\u5355\u7ebf\u7a0b\u6267\u884c\u89c6\u89d2\u4e0b，\u5148\u8d4b\u503c\u6307\u9488\u8fd8\u662f\u5148\u6784\u9020\u5185\u5b58，\u5bf9\u4e8e\u5f53\u524d\u7ebf\u7a0b\u81ea\u8eab\u800c\u8a00\u6ca1\u6709\u4efb\u4f55\u53ef\u89c2\u6d4b\u7684\u526f\u4f5c\u7528\u3002\u56e0\u6b64，\u73b0\u4ee3\u4f18\u5316\u7f16\u8bd1\u5668\u4e3a\u4e86\u6700\u5927\u5316\u5bc4\u5b58\u5668\u5206\u914d\u6548\u7387，\u6216\u8005\u8d85\u6807\u91cf\u5904\u7406\u5668\u7684\u4e71\u5e8f\u6267\u884c\u5f15\u64ce（Out-of-Order Engine）\u4e3a\u4e86\u9690\u85cf\u6784\u9020\u51fd\u6570\u6df1\u5c42\u5199\u5165\u7684\u5ef6\u8fdf，\u5b8c\u5168\u6709\u5408\u6cd5\u7684\u81ea\u7531\u5c06\u6b65\u9aa4 3 \u63d0\u524d\u53d1\u5c04！<\/p>\n
\u4e00\u65e6\u53d1\u751f\u8fd9\u79cd\u91cd\u6392，\u5bf9\u4e8e\u53e6\u4e00\u4e2a\u5b8c\u5168\u5728\u65e0\u9501\u72b6\u6001\u4e0b\u8bfb\u53d6 instance \u7684\u7ebf\u7a0b\u800c\u8a00，\u5b83\u770b\u5230\u7684\u4fbf\u662f\u4e00\u4e2a\u201c\u5df2\u7ecf\u66b4\u9732\u3001\u5374\u672a\u5b8c\u5168\u6210\u578b\u201d\u7684\u81f4\u547d\u602a\u80ce\u3002<\/p>\n
\u89e3\u51b3\u8fd9\u4e00\u56f0\u5883\u7684\u6570\u5b66\u6838\u5fc3，\u662f\u5728\u201c\u5199\u7ebf\u7a0b\u201d\u4e0e\u201c\u8bfb\u7ebf\u7a0b\u201d\u4e4b\u95f4\u5efa\u7acb\u8d77\u8de8\u6838\u5fc3\u7684\u540c\u6b65\u4e0e\u5148\u884c\u56e0\u679c\u5173\u7cfb（Synchronizes-With & Happens-Before）\u3002<\/p>\n
\u8fd9\u6b63\u662f C++11 \u5f15\u5165\u3001\u5e76\u5728 C++23 \u4e2d\u6301\u7eed\u4f5c\u4e3a\u6838\u5fc3\u57fa\u77f3\u7684\u539f\u5b50\u5185\u5b58\u987a\u5e8f\u6240\u5b9a\u4e49\u7684\u795e\u5723\u5951\u7ea6：<\/p>\n
Acquire-Release \u5efa\u7acb\u7684\u8de8\u6838\u5185\u5b58\u5c4f\u969c:
\nThread 1 (\u5199\u7ebf\u7a0b):
\n [ \u6b65\u9aa4 1: \u5185\u5b58\u5206\u914d ]
\n [ \u6b65\u9aa4 2: \u6784\u9020\u51fd\u6570\u6240\u6709\u6210\u5458\u53d8\u91cf\u5199\u5165 ]
\n ——————————— [ \u5185\u5b58\u5c4f\u969c: memory_order_release ]
\n [ \u6b65\u9aa4 3: instance.store(ptr, release) ]
\n |
\n | (\u786c\u4ef6\u5c42\u4fdd\u8bc1: \u5c4f\u969c\u4e4b\u4e0a\u7684\u5168\u90e8\u5199\u64cd\u4f5c，\u5728\u53d1\u5e03\u6307\u9488\u65f6\u5df2\u7edd\u5bf9\u843d\u76d8\u53ef\u89c1！)
\n v
\nThread 2 (\u8bfb\u7ebf\u7a0b):
\n [ instance.load(acquire) ]
\n ——————————— [ \u5185\u5b58\u5c4f\u969c: memory_order_acquire ]
\n [ \u8bfb\u53d6 instance \u5185\u90e8\u7684\u6210\u5458\u53d8\u91cf ]
\n (\u786c\u4ef6\u5c42\u4fdd\u8bc1: \u7edd\u4e0d\u91cd\u6392\u5230 acquire \u4e4b\u524d，\u5fc5\u5b9a\u770b\u5230 Thread 1 \u5728 release \u4e4b\u524d\u7684\u6240\u6709\u5199\u5165！)<\/p>\n
\u4ee5\u4e0b\u4ee3\u7801\u6f14\u793a\u4e86\u5b8c\u5168\u7b26\u5408 C++ \u6807\u51c6\u3001\u5177\u5907\u7edd\u5bf9\u5fae\u67b6\u6784\u5b89\u5168\u6027\u7684\u5de5\u4e1a\u7ea7 DCLP \u5b9e\u73b0：<\/p>\n
#include <iostream>
\n#include <atomic>
\n#include <mutex>
\n#include <string>
\n#include <cstdint>
\n#include <cassert><\/p>\n
class GlobalTensorEngine {
\nprivate:
\n \/\/ \u5fc5\u987b\u58f0\u660e\u4e3a\u539f\u5b50\u6307\u9488，\u5f7b\u5e95\u6d88\u9664\u6570\u636e\u7ade\u4e89
\n static inline std::atomic<GlobalTensorEngine*> instance_{nullptr};
\n static inline std::mutex init_mutex_{};<\/p>\n
\/\/ \u5355\u4f8b\u5185\u90e8\u590d\u6742\u72b6\u6001
\n uint64_t engine_id_{0};
\n std::string config_name_{};
\n bool is_hardware_locked_{false};<\/p>\n
\/\/ \u79c1\u6709\u6784\u9020\u51fd\u6570
\n GlobalTensorEngine(uint64_t id, std::string cfg)
\n : engine_id_(id), config_name_(std::move(cfg)), is_hardware_locked_(true) {
\n std::cout << "[DCLP] \u590d\u6742\u5355\u4f8b\u786c\u4ef6\u73af\u5883\u6b63\u5728\u521d\u59cb\u5316，\u5b8c\u6210\u7269\u7406\u5bc4\u5b58\u5668\u9501\u5b9a…\\\\n";
\n }<\/p>\n
public:
\n ~GlobalTensorEngine() = default;
\n GlobalTensorEngine(const GlobalTensorEngine&) = delete;
\n GlobalTensorEngine& operator=(const GlobalTensorEngine&) = delete;<\/p>\n
\/\/ \u5de5\u4e1a\u7ea7 DCLP \u7ec8\u6781\u5b89\u5168\u83b7\u53d6\u51fd\u6570
\n static GlobalTensorEngine* get_instance() noexcept {
\n \/\/ \u7b2c 1 \u91cd\u68c0\u67e5: \u91c7\u7528 Acquire \u8bed\u4e49\u8bfb\u53d6！
\n \/\/ \u4fdd\u8bc1\u53ea\u8981\u8bfb\u5230\u4e86\u975e\u7a7a，\u540e\u7eed\u5bf9\u5355\u4f8b\u6210\u5458\u7684\u8bbf\u95ee\u7edd\u5bf9\u5b89\u5168\u53ef\u89c1！
\n GlobalTensorEngine* ptr = instance_.load(std::memory_order_acquire);<\/p>\n
\/\/ \u5feb\u8def\u5f84 (Happy Path): \u7edd\u5927\u591a\u6570\u65f6\u523b\u6307\u9488\u5df2\u521d\u59cb\u5316，\u5355\u6761\u65e0\u9501\u6307\u4ee4\u76f4\u63a5\u8fd4\u56de！
\n if (ptr == nullptr) {
\n \/\/ \u6162\u8def\u5f84 (Cold Path): \u52a0\u4e92\u65a5\u9501\u8fdb\u884c\u53cc\u91cd\u6821\u9a8c
\n std::lock_guard<std::mutex> lock(init_mutex_);
\n \/\/ \u7b2c 2 \u91cd\u68c0\u67e5: \u91c7\u7528 Relaxed \u5373\u53ef，\u56e0\u4e3a\u5904\u4e8e\u4e92\u65a5\u9501\u7684\u5b8c\u5168\u4fdd\u62a4\u4f1e\u4e0b
\n ptr = instance_.load(std::memory_order_relaxed);<\/p>\n
if (ptr == nullptr) {
\n \/\/ \u539f\u5730\u6784\u9020\u590d\u6742\u5bf9\u8c61
\n auto* new_instance = new GlobalTensorEngine(1024, "Sapphire_Rapids_AVX512");<\/p>\n
\/\/ \u6838\u5fc3\u5173\u952e: \u91c7\u7528 Release \u8bed\u4e49\u53d1\u5e03\u6307\u9488！
\n \/\/ \u5f7b\u5e95\u963b\u65ad\u6307\u4ee4\u91cd\u6392，\u786e\u4fdd\u6784\u9020\u51fd\u6570\u7684\u5199\u5165\u7edd\u5bf9\u5148\u884c\u4e8e\u6307\u9488\u7684\u53ef\u89c1\u6027！
\n instance_.store(new_instance, std::memory_order_release);
\n ptr = new_instance;
\n }
\n }<\/p>\n
return ptr;
\n }<\/p>\n
void execute_operator() const noexcept {
\n assert(is_hardware_locked_ && "\u81f4\u547d\u9519\u8bef: \u89c2\u6d4b\u5230\u4e86\u534a\u521d\u59cb\u5316\u5bf9\u8c61！");
\n \/\/ \u5b89\u5168\u6267\u884c…
\n }
\n};<\/p>\n
\u5728\u73b0\u4ee3 C++（C++11 \u4ee5\u540e）\u4e2d，\u6807\u51c6\u63d0\u51fa\u4e86\u8457\u540d\u7684\u201cMagic Static（\u9759\u6001\u5c40\u90e8\u53d8\u91cf\u7ebf\u7a0b\u5b89\u5168\u89c4\u8303）\u201d：<\/p>\n
GlobalTensorEngine& get_magic_instance() {
\n static GlobalTensorEngine instance(1024, "Magic_Static");
\n return instance;
\n}<\/p>\n
\u5f88\u591a\u4eba\u77e5\u9053 Magic Static \u662f\u7ebf\u7a0b\u5b89\u5168\u7684，\u5374\u4e0d\u77e5\u9053\u73b0\u4ee3\u7f16\u8bd1\u5668\u5728\u5e95\u5c42\u662f\u5982\u4f55\u5b9e\u73b0\u5b83\u7684\u2014\u2014\u5176\u5e95\u5c42\u673a\u5668\u7801\u6070\u6070\u5c31\u662f\u6211\u4eec\u4e0a\u8ff0\u624b\u5199\u7684 DCLP \u7684\u5de5\u4e1a\u7ea7\u5c01\u88c5！<\/p>\n
\u5ba1\u89c6 GCC 14 \u5bf9 Magic Static \u751f\u6210\u7684\u6838\u5fc3\u6c47\u7f16\u4ee3\u7801：<\/p>\n
# Magic Static \u5e95\u5c42\u751f\u6210\u7684\u673a\u5668\u7801:
\n movzbl _ZGVZ19get_magic_instancevE8instance(%rip), %eax # (1) \u68c0\u67e5\u4fdd\u62a4\u6807\u5fd7 Guard Flag (Acquire)
\n testb %al, %al
\n je .Lslow_init # \u4e3a\u7a7a\u5219\u8fdb\u5165\u6162\u901f\u521d\u59cb\u5316
\n movq _ZZ19get_magic_instancevE8instance(%rip), %rax # \u5df2\u7ecf\u521d\u59cb\u5316，\u76f4\u63a5\u8fd4\u56de！
\n ret<\/p>\n
.Lslow_init:
\n call __cxa_guard_acquire # (2) \u7c7b\u4f3c\u4e8e\u52a0\u4e92\u65a5\u9501
\n testl %eax, %eax
\n je .Ldone
\n call GlobalTensorEngine::GlobalTensorEngine(…) # (3) \u8c03\u7528\u6784\u9020\u51fd\u6570
\n call __cxa_guard_release # (4) Release \u8bed\u4e49\u53d1\u5e03\u6807\u5fd7<\/p>\n
\u7f16\u8bd1\u5668\u5e95\u5c42\u81ea\u52a8\u751f\u6210\u4e86\u4e00\u4e2a\u9690\u5f0f\u7684 __cxa_guard_acquire \u4e0e __cxa_guard_release，\u8fd9\u4ece\u786c\u4ef6\u673a\u5668\u7801\u5c42\u9762\u5f7b\u5e95\u5370\u8bc1\u4e86\u6211\u4eec\u7684\u7406\u8bba\u63a8\u5bfc：\u6ca1\u6709 Acquire-Release \u5c4f\u969c，\u5c31\u6839\u672c\u65e0\u6cd5\u5728\u7269\u7406\u591a\u6838\u82af\u7247\u4e0a\u6784\u5efa\u6b63\u786e\u7684\u53cc\u91cd\u68c0\u67e5\u5355\u4f8b！<\/p>\n
\u53cc\u91cd\u68c0\u67e5\u9501\u5b9a\u6a21\u5f0f（DCLP）\u4e0d\u4ec5\u662f\u4e00\u6bb5\u5173\u4e8e\u8bbe\u8ba1\u6a21\u5f0f\u7684\u7ecf\u5178\u6848\u4f8b，\u66f4\u662f\u901a\u5f80\u73b0\u4ee3\u4f53\u7cfb\u7ed3\u6784\u3001\u7f16\u8bd1\u5668\u4f18\u5316\u4e0e\u5185\u5b58\u6a21\u578b\u6df1\u5904\u7684\u4e00\u9762\u900f\u89c6\u955c\u3002\u5b83\u65e0\u60c5\u5730\u6233\u7834\u4e86\u201c\u9ad8\u7ea7\u8bed\u8a00\u8bed\u6cd5\u4ee3\u8868\u673a\u5668\u7269\u7406\u884c\u4e3a\u201d\u7684\u6d45\u663e\u5047\u8c61，\u5c06\u73b0\u4ee3\u8d85\u6807\u91cf CPU \u4e71\u5e8f\u6267\u884c\u4e0e\u591a\u7ea7\u5199\u7f13\u51b2\u533a\u7684\u51b0\u51b7\u73b0\u5b9e\u5c55\u73b0\u5728\u6211\u4eec\u9762\u524d\u3002\u7406\u89e3\u5e76\u7cbe\u901a Acquire-Release \u8bed\u4e49\u5728 DCLP \u4e2d\u7684\u7edd\u5bf9\u56e0\u679c\u5f8b，\u662f\u6bcf\u4e00\u4f4d\u81f4\u529b\u4e8e\u7cfb\u7edf\u7ea7\u6838\u5fc3\u57fa\u7840\u8bbe\u65bd\u7814\u53d1\u7684\u5de5\u7a0b\u5e08\u5efa\u7acb\u8d77\u575a\u4e0d\u53ef\u6467\u5e76\u53d1\u76f4\u89c9\u7684\u5fc5\u4fee\u4e4b\u8bfe\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u5728\u5e76\u53d1\u7f16\u7a0b\u7684\u53d1\u5c55\u53f2\u4e2d，**\u53cc\u91cd\u68c0\u67e5\u9501\u5b9a\u6a21\u5f0f（Double-Checked Locking Pattern, \u7b80\u79f0 DCLP）**\u662f\u4e00\u5ea7\u88ab\u65e0\u6570\u6280\u672f\u5148\u8d24\u53cd\u590d\u89e3\u5256\u3001\u5374\u4f9d\u7136\u5728\u73b0\u4ee3\u591a\u6838\u670d\u52a1\u5668\u4e0a\u9891\u7e41\u5236\u9020\u7ebf\u4e0a\u5d29\u6e83\u7684\u201c\u7ecf\u5178\u8ff7\u5bab\u201d\u3002
\n\u5176\u6700\u521d\u7684\u8bbe\u8ba1\u52a8\u673a\u6781\u5176\u5355\u7eaf\u800c\u4f18\u96c5：\u4e3a\u4e86\u5728\u591a\u7ebf\u7a0b\u73af\u5883\u4e0b\u5b9e\u73b0\u61d2\u52a0\u8f7d（Lazy Initialization）\u5355\u4f8b\u6a21\u5f0f，\u540c\u65f6\u907f\u514d\u6bcf\u6b21\u83b7\u53d6\u5355\u4f8b\u90fd\u7ecf\u5386\u4e92\u65a5\u9501（std<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[66,50,292,100,51],"topic":[],"class_list":["post-116791","post","type-post","status-publish","format-standard","hentry","category-server","tag-ai","tag-50","tag-292","tag-100","tag-51"],"yoast_head":"\n