{"id":7438,"date":"2026-07-22T12:28:38","date_gmt":"2026-07-22T04:28:38","guid":{"rendered":"https:\/\/i007.cc\/wordpress\/?p=7438"},"modified":"2026-07-22T12:28:38","modified_gmt":"2026-07-22T04:28:38","slug":"cache-friendly-%e6%95%b0%e6%8d%ae%e7%bb%93%e6%9e%84%e8%ae%be%e8%ae%a1","status":"publish","type":"post","link":"https:\/\/i007.cc\/wordpress\/archives\/7438","title":{"rendered":"Cache-Friendly \u6570\u636e\u7ed3\u6784\u8bbe\u8ba1"},"content":{"rendered":"
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<\/h3>\n

\ud83d\udd37 \u4e00\u3001\u4e3a\u4ec0\u4e48 Cache \u8fd9\u4e48\u91cd\u8981\uff1f<\/h3>\n
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CPU \u5bc4\u5b58\u5668\u8bbf\u95ee\uff1a      ~1 \u4e2a\u5468\u671f\r\nL1 Cache \u8bbf\u95ee\uff1a       ~4 \u4e2a\u5468\u671f\r\nL2 Cache \u8bbf\u95ee\uff1a       ~12 \u4e2a\u5468\u671f\r\nL3 Cache \u8bbf\u95ee\uff1a       ~40 \u4e2a\u5468\u671f\r\n\u4e3b\u5185\u5b58\uff08RAM\uff09\u8bbf\u95ee\uff1a    ~200+ \u4e2a\u5468\u671f<\/pre>\n
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\u5185\u5b58\u8bbf\u95ee\u6bd4 L1 \u7f13\u5b58\u6162 50 \u500d\u4ee5\u4e0a\uff01<\/strong> \u5982\u679c\u4f60\u7684\u6570\u636e\u7ed3\u6784\u8ba9 CPU \u9891\u7e41”\u7f13\u5b58\u672a\u547d\u4e2d”\uff08cache miss\uff09\uff0c\u4ee3\u7801\u903b\u8f91\u518d\u4f18\u96c5\uff0c\u6027\u80fd\u4e5f\u4f1a\u88ab\u5185\u5b58\u5ef6\u8fdf\u62d6\u57ae\u3002<\/p>\n<\/blockquote>\n
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\ud83d\udd37 \u4e8c\u3001\u6838\u5fc3\u539f\u7406\uff1a\u7f13\u5b58\u884c\uff08Cache Line\uff09<\/h3>\n
CPU \u4ece\u5185\u5b58\u8bfb\u6570\u636e\u65f6\uff0c\u4e0d\u662f\u6309\u5b57\u8282\u8bfb\uff0c\u800c\u662f\u6309”\u7f13\u5b58\u884c”\u6279\u91cf\u8bfb\u53d6<\/strong>\uff08\u901a\u5e38 64 \u5b57\u8282\uff09\u3002<\/p>\n
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\u5185\u5b58\u5730\u5740\uff1a  [0..63]\u5b57\u8282  [64..127]\u5b57\u8282  [128..191]\u5b57\u8282\r\n              \u2193 \u4e00\u6b21\u6027\u52a0\u8f7d\u5230 L1\r\n            \u7f13\u5b58\u884c1        \u7f13\u5b58\u884c2          \u7f13\u5b58\u884c3<\/pre>\n
 <\/p>\n<\/div>\n<\/div>\n
\u5173\u952e\u542f\u793a<\/strong>\uff1a\u5982\u679c\u4f60\u8bbf\u95ee\u5730\u5740 0x1000<\/code>\uff0cCPU \u4f1a\u987a\u4fbf\u628a 0x1000~0x103F<\/code>\uff0864\u5b57\u8282\uff09\u90fd\u52a0\u8f7d\u8fdb\u7f13\u5b58\u3002\u63a5\u4e0b\u6765\u5982\u679c\u8bbf\u95ee\u7684\u6570\u636e\u6070\u597d\u5728\u8fd964\u5b57\u8282\u5185\uff0c\u51e0\u4e4e\u96f6\u5ef6\u8fdf\uff1b\u5982\u679c\u8df3\u5230\u5f88\u8fdc\u7684\u5730\u65b9\uff0c\u53c8\u662f\u4e00\u6b21\u6602\u8d35\u7684\u5185\u5b58\u8bbf\u95ee\u3002<\/strong><\/p>\n
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\ud83d\udd37 \u4e09\u3001\u7ecf\u5178\u6848\u4f8b\uff1a\u6570\u7ec4 vs \u94fe\u8868<\/h3>\n
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cpp<\/div>\n
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\/\/ \u6570\u7ec4\uff1a\u5185\u5b58\u8fde\u7eed\r\nstd::vector<int> arr = {1, 2, 3, 4, 5, ...};\r\n\/\/ \u5185\u5b58\u5e03\u5c40\uff1a[1][2][3][4][5]... \u7d27\u5bc6\u6392\u5217\r\n\r\n\/\/ \u94fe\u8868\uff1a\u5185\u5b58\u5206\u6563\r\nstd::list<int> lst = {1, 2, 3, 4, 5, ...};\r\n\/\/ \u5185\u5b58\u5e03\u5c40\uff1a[1]\u2192(\u968f\u673a\u5730\u5740)\u2192[2]\u2192(\u968f\u673a\u5730\u5740)\u2192[3]...<\/pre>\n
 <\/p>\n<\/div>\n<\/div>\n
\u6027\u80fd\u5b9e\u6d4b\uff08\u5178\u578b\u7ed3\u679c\uff09<\/h4>\n
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cpp<\/div>\n
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\/\/ \u904d\u53861000\u4e07\u4e2aint\u6c42\u548c\r\n\r\nstd::vector<int> v(10000000);\r\nint sum = 0;\r\nfor (int x : v) sum += x;\r\n\/\/ \u8017\u65f6\uff1a~5ms\uff08\u7f13\u5b58\u547d\u4e2d\u7387\u6781\u9ad8\uff0c\u6570\u636e\u8fde\u7eed\uff09\r\n\r\nstd::list<int> l(10000000);\r\nfor (int x : l) sum += x;\r\n\/\/ \u8017\u65f6\uff1a~50-80ms\uff01\uff08\u6bcf\u6b21\u8df3\u8f6c\u53ef\u80fd\u662f\u4e00\u6b21\u7f13\u5b58\u672a\u547d\u4e2d\uff09<\/pre>\n
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\u5373\u4f7f\u4e24\u8005\u65f6\u95f4\u590d\u6742\u5ea6\u90fd\u662f O(n)\uff0c\u5b9e\u9645\u6027\u80fd\u53ef\u4ee5\u76f8\u5dee 10\u500d\u4ee5\u4e0a\uff01<\/strong> \u8fd9\u5c31\u662f\u4e3a\u4ec0\u4e48\u73b0\u4ee3 C++ \u63a8\u8350”\u9ed8\u8ba4\u7528 vector<\/code>\uff0c\u9664\u975e\u6709\u660e\u786e\u7406\u7531\u7528 list<\/code><\/strong>“\u3002<\/p>\n<\/blockquote>\n
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\ud83d\udd37 \u56db\u3001Structure of Arrays (SoA) vs Array of Structures (AoS)<\/h3>\n
\u8fd9\u662f cache-friendly \u8bbe\u8ba1\u4e2d\u6700\u91cd\u8981\u7684\u4e00\u4e2a\u6743\u8861<\/strong>\u3002<\/p>\n
AoS\uff08\u76f4\u89c9\u5199\u6cd5\uff0c\u4f46\u53ef\u80fd\u4e0d\u662f\u6700\u4f18\uff09<\/h4>\n
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cpp<\/div>\n
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struct Particle {\r\n    float x, y, z;       \/\/ \u4f4d\u7f6e\r\n    float vx, vy, vz;    \/\/ \u901f\u5ea6\r\n    float mass;\r\n    int id;\r\n};\r\n\r\nstd::vector<Particle> particles(10000);\r\n\r\n\/\/ \u53ea\u9700\u8981\u66f4\u65b0\u4f4d\u7f6e\uff0c\u4f46\u6bcf\u6b21\u90fd\u8981\u628a\u6574\u4e2a Particle\uff08\u542b\u901f\u5ea6\u3001\u8d28\u91cf\u7b49\uff09\u52a0\u8f7d\u8fdb\u7f13\u5b58\r\nfor (auto& p : particles) {\r\n    p.x += p.vx;\r\n    p.y += p.vy;\r\n    p.z += p.vz;\r\n}<\/pre>\n
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\u5185\u5b58\u5e03\u5c40\uff1a<\/p>\n
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[x y z vx vy vz mass id][x y z vx vy vz mass id]...\r\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500 Particle 1 \u2500\u2500\u2500\u2500\u2500\u2518\u2514\u2500\u2500\u2500\u2500\u2500\u2500 Particle 2 \u2500\u2500\u2500\u2500\u2500\u2518<\/pre>\n
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\u95ee\u9898<\/strong>\uff1a\u54ea\u6015\u53ea\u7528\u5230 x,y,z,vx,vy,vz<\/code>\uff0c\u7f13\u5b58\u884c\u91cc\u6df7\u8fdb\u4e86\u4e0d\u9700\u8981\u7684 mass<\/code>\u3001id<\/code>\uff0c\u9020\u6210”\u65e0\u6548\u6570\u636e\u5360\u7528\u7f13\u5b58\u7a7a\u95f4”\u3002<\/p>\n
SoA\uff08\u6309\u5b57\u6bb5\u62c6\u5206\uff0ccache-friendly\uff09<\/h4>\n
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cpp<\/div>\n
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struct ParticleSystem {\r\n    std::vector<float> x, y, z;\r\n    std::vector<float> vx, vy, vz;\r\n    std::vector<float> mass;\r\n    std::vector<int> id;\r\n};\r\n\r\nParticleSystem particles;\r\n\r\n\/\/ \u53ea\u8bbf\u95ee\u9700\u8981\u7684\u6570\u7ec4\uff0c\u7f13\u5b58\u884c\u91cc\u5168\u662f\u6709\u7528\u6570\u636e\r\nfor (size_t i = 0; i < particles.x.size(); i++) {\r\n    particles.x[i] += particles.vx[i];\r\n    particles.y[i] += particles.vy[i];\r\n    particles.z[i] += particles.vz[i];\r\n}<\/pre>\n
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\u5185\u5b58\u5e03\u5c40\uff1a<\/p>\n
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x: [x1][x2][x3][x4]...   \u2190 \u8fde\u7eed\uff0c\u5168\u662fx\u5750\u6807\uff0c\u7f13\u5b58\u5229\u7528\u7387100%\r\ny: [y1][y2][y3][y4]...\r\nvx:[vx1][vx2][vx3]...<\/pre>\n
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\u5178\u578b\u573a\u666f<\/strong>\uff1a\u6e38\u620f\u5f15\u64ce\u3001\u7269\u7406\u6a21\u62df\u3001\u5411\u91cf\u5316\u8ba1\u7b97\uff08SIMD\uff09\uff0cSoA \u5f80\u5f80\u6bd4 AoS \u5feb 2-4\u500d<\/strong>\uff0c\u56e0\u4e3a\uff1a<\/p>\n
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  1. \u7f13\u5b58\u884c\u4e0d\u6d6a\u8d39\u5728”\u7528\u4e0d\u5230\u7684\u5b57\u6bb5”\u4e0a<\/li>\n
  2. \u7f16\u8bd1\u5668\u66f4\u5bb9\u6613\u505a SIMD \u81ea\u52a8\u5411\u91cf\u5316\uff08\u540c\u7c7b\u578b\u6570\u636e\u8fde\u7eed\u6392\u5217\uff09<\/li>\n<\/ol>\n<\/blockquote>\n
    \u4ec0\u4e48\u65f6\u5019 AoS \u53cd\u800c\u66f4\u597d\uff1f<\/h4>\n
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    cpp<\/div>\n
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    \/\/ \u5982\u679c\u4f60\u603b\u662f\"\u6574\u4f53\"\u8bbf\u95ee\u4e00\u4e2a\u5bf9\u8c61\u7684\u6240\u6709\u5b57\u6bb5\r\nfor (auto& p : particles) {\r\n    render(p.x, p.y, p.z, p.color, p.texture);  \/\/ \u7528\u5230\u51e0\u4e4e\u6240\u6709\u5b57\u6bb5\r\n}<\/pre>\n
     <\/p>\n<\/div>\n<\/div>\n
    \u8fd9\u79cd\u60c5\u51b5\u4e0b AoS \u66f4\u5408\u9002\u2014\u2014\u56e0\u4e3a\u4e00\u6b21\u7f13\u5b58\u884c\u52a0\u8f7d\u5c31\u62ff\u5230\u4e86\u6240\u6709\u9700\u8981\u7684\u6570\u636e\u3002<\/p>\n
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    \u6cd5\u5219\uff1a\u8bbf\u95ee\u6a21\u5f0f\u51b3\u5b9a\u5e03\u5c40\u3002”\u6309\u5b57\u6bb5\u6279\u91cf\u5904\u7406” \u2192 SoA\uff1b”\u6309\u5bf9\u8c61\u6574\u4f53\u5904\u7406” \u2192 AoS\u3002<\/strong><\/p>\n<\/blockquote>\n
    \n
    \ud83d\udd37 \u4e94\u3001\u907f\u514d”\u4f2a\u5171\u4eab”\uff08False Sharing\uff09\u2014\u2014 \u591a\u7ebf\u7a0b\u573a\u666f\u7684\u9690\u5f62\u6740\u624b<\/h3>\n
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    cpp<\/div>\n
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    struct Counters {\r\n    std::atomic<int> counterA;  \/\/ \u7ebf\u7a0b1\u9891\u7e41\u5199\r\n    std::atomic<int> counterB;  \/\/ \u7ebf\u7a0b2\u9891\u7e41\u5199\r\n};\r\nCounters c;\r\n\r\n\/\/ \u7ebf\u7a0b1\r\nwhile (true) c.counterA++;\r\n\r\n\/\/ \u7ebf\u7a0b2\r\nwhile (true) c.counterB++;<\/pre>\n
     <\/p>\n<\/div>\n<\/div>\n
    \u95ee\u9898<\/strong>\uff1acounterA<\/code> \u548c counterB<\/code> \u5927\u6982\u7387\u843d\u5728\u540c\u4e00\u6761\u7f13\u5b58\u884c<\/strong>\u91cc\uff08\u7f13\u5b58\u884c64\u5b57\u8282\uff0c\u4e24\u4e2aint\u53ea\u53608\u5b57\u8282\uff09\u3002<\/p>\n
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    \u7f13\u5b58\u884c: [counterA][counterB][padding...........]\r\n         \u2191\u7ebf\u7a0b1\u5199            \u2191\u7ebf\u7a0b2\u5199<\/pre>\n
     <\/p>\n<\/div>\n<\/div>\n
    CPU \u7684\u7f13\u5b58\u4e00\u81f4\u6027\u534f\u8bae\uff08MESI\uff09\u8981\u6c42\uff1a\u4e00\u4e2a\u6838\u5fc3\u5199\u4e86\u8fd9\u6761\u7f13\u5b58\u884c\uff0c\u5176\u4ed6\u6838\u5fc3\u7684\u7f13\u5b58\u526f\u672c\u5fc5\u987b\u5931\u6548<\/strong>\u3002\u4e8e\u662f\u7ebf\u7a0b1\u5199 counterA<\/code> \u4f1a\u8ba9\u7ebf\u7a0b2\u7f13\u5b58\u7684\u6574\u6761\u7f13\u5b58\u884c\u5931\u6548\uff08\u54ea\u6015\u5b83\u6ca1\u78b0 counterA<\/code>\uff09\uff0c\u53cd\u4e4b\u4ea6\u7136\u2014\u2014\u4e24\u4e2a\u6beb\u4e0d\u76f8\u5173\u7684\u53d8\u91cf\uff0c\u56e0\u4e3a”\u4f4f\u5f97\u592a\u8fd1”\u800c\u4e92\u76f8\u62d6\u7d2f\u6027\u80fd<\/strong>\u3002<\/p>\n
    \u89e3\u51b3\uff1a\u624b\u52a8\u586b\u5145\u5bf9\u9f50\uff0c\u8ba9\u5b83\u4eec\u5404\u5360\u4e00\u6761\u7f13\u5b58\u884c<\/h4>\n
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    cpp<\/div>\n
    \n
    struct alignas(64) PaddedCounter {   \/\/ \u5f3a\u523664\u5b57\u8282\u5bf9\u9f50\r\n    std::atomic<int> value;\r\n    char padding[64 - sizeof(std::atomic<int>)];  \/\/ \u586b\u5145\u6ee1\u4e00\u6761\u7f13\u5b58\u884c\r\n};\r\n\r\nstruct Counters {\r\n    PaddedCounter counterA;\r\n    PaddedCounter counterB;\r\n};<\/pre>\n
     <\/p>\n<\/div>\n<\/div>\n
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    \u7f13\u5b58\u884c1: [counterA][padding..................]  \u2190 \u72ec\u5360\u4e00\u6761\u7f13\u5b58\u884c\r\n\u7f13\u5b58\u884c2: [counterB][padding..................]  \u2190 \u72ec\u5360\u4e00\u6761\u7f13\u5b58\u884c<\/pre>\n
     <\/p>\n<\/div>\n<\/div>\n
    \u73b0\u5728\u4e24\u4e2a\u7ebf\u7a0b\u4e92\u4e0d\u5e72\u6270\uff0c\u5b9e\u6d4b\u6027\u80fd\u63d0\u5347\u53ef\u8fbe 5-10\u500d<\/strong>\uff08\u9ad8\u5e76\u53d1\u8ba1\u6570\u5668\u573a\u666f\uff09\u3002<\/p>\n
    \n
    C++17 \u8d77\u4e5f\u53ef\u4ee5\u7528 std::hardware_destructive_interference_size<\/code> \u4ee3\u66ff\u786c\u7f16\u7801\u768464\uff1a<\/p>\n<\/blockquote>\n
    \n
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    <\/div>\n<\/div>\n
    cpp<\/div>\n
    \n
    struct alignas(std::hardware_destructive_interference_size) PaddedCounter {\r\n    std::atomic<int> value;\r\n};<\/pre>\n
     <\/p>\n<\/div>\n<\/div>\n
    \n
    \ud83d\udd37 \u516d\u3001\u51cf\u5c11\u6307\u9488\u8ffd\u9010\uff08Pointer Chasing\uff09<\/h3>\n
    \n
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    <\/div>\n<\/div>\n
    cpp<\/div>\n
    \n
    \/\/ \u274c \u94fe\u5f0f\u7ed3\u6784\uff1a\u6bcf\u6b21\u89e3\u5f15\u7528\u90fd\u53ef\u80fd\u662f\u4e00\u6b21\u7f13\u5b58\u672a\u547d\u4e2d\r\nstruct TreeNode {\r\n    int value;\r\n    TreeNode* left;\r\n    TreeNode* right;\r\n};\r\n\/\/ \u904d\u5386\u6811\u65f6\uff0c\u6bcf\u8df3\u4e00\u6b21\u6307\u9488\u90fd\u53ef\u80fd\u8df3\u5230\u5185\u5b58\u4e2d\u5f88\u8fdc\u7684\u5730\u65b9\r\n\r\n\/\/ \u2705 \u7528\u6241\u5e73\u6570\u7ec4\u6a21\u62df\u6811\uff08\u5982\u679c\u7ed3\u6784\u76f8\u5bf9\u56fa\u5b9a\uff0c\u6bd4\u5982\u5b8c\u5168\u4e8c\u53c9\u6811\uff09\r\nstd::vector<int> heap;  \/\/ \u7236\u8282\u70b9i\uff0c\u5de6\u5b50=2i+1\uff0c\u53f3\u5b50=2i+2\r\n\/\/ \u6574\u68f5\u6811\u8fde\u7eed\u5b58\u50a8\u5728\u4e00\u4e2a\u6570\u7ec4\u91cc\uff0c\u904d\u5386\u65f6\u7f13\u5b58\u547d\u4e2d\u7387\u5927\u5e45\u63d0\u5347<\/pre>\n
     <\/p>\n<\/div>\n<\/div>\n
    \u8fd9\u6b63\u662f\u5806\uff08heap\uff09\u6570\u636e\u7ed3\u6784<\/strong>\u7528\u6570\u7ec4\u800c\u4e0d\u662f\u94fe\u5f0f\u8282\u70b9\u5b9e\u73b0\u7684\u539f\u56e0\u4e4b\u4e00\u3002<\/p>\n
    \n
    \ud83d\udd37 \u4e03\u3001\u5bf9\u9f50\u4e0e\u7d27\u51d1\u5e03\u5c40\uff08\u907f\u514d Padding \u6d6a\u8d39\uff09<\/h3>\n
    \n
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    <\/div>\n<\/div>\n
    cpp<\/div>\n
    \n
    \/\/ \u274c \u5b57\u6bb5\u987a\u5e8f\u4e0d\u5408\u7406\uff0c\u7f16\u8bd1\u5668\u88ab\u8feb\u63d2\u5165\u5927\u91cf padding\r\nstruct BadLayout {\r\n    char a;      \/\/ 1\u5b57\u8282\r\n    \/\/ 7\u5b57\u8282 padding\uff08\u4e3a\u4e86\u8ba9 double 8\u5b57\u8282\u5bf9\u9f50\uff09\r\n    double b;    \/\/ 8\u5b57\u8282\r\n    char c;      \/\/ 1\u5b57\u8282\r\n    \/\/ 7\u5b57\u8282 padding\r\n};\r\n\/\/ sizeof(BadLayout) = 24 \u5b57\u8282\uff08\u5b9e\u9645\u6709\u6548\u6570\u636e\u53ea\u670910\u5b57\u8282\uff01\uff09\r\n\r\n\/\/ \u2705 \u6309\u5927\u5c0f\u4ece\u5927\u5230\u5c0f\u6392\u5217\u5b57\u6bb5\uff0c\u51cf\u5c11 padding\r\nstruct GoodLayout {\r\n    double b;    \/\/ 8\u5b57\u8282\r\n    char a;      \/\/ 1\u5b57\u8282\r\n    char c;      \/\/ 1\u5b57\u8282\r\n    \/\/ 6\u5b57\u8282 padding\uff08\u53ea\u9700\u8865\u52308\u7684\u500d\u6570\uff09\r\n};\r\n\/\/ sizeof(GoodLayout) = 16 \u5b57\u8282<\/pre>\n
     <\/p>\n<\/div>\n<\/div>\n
    \n
    cpp<\/div>\n
    \n
    \/\/ \u9a8c\u8bc1\r\nstd::cout << sizeof(BadLayout);   \/\/ 24\r\nstd::cout << sizeof(GoodLayout);  \/\/ 16<\/pre>\n
     <\/p>\n<\/div>\n<\/div>\n
    \u66f4\u7d27\u51d1\u7684\u7ed3\u6784 = \u4e00\u6761\u7f13\u5b58\u884c\u80fd\u585e\u4e0b\u66f4\u591a\u5bf9\u8c61 = \u66f4\u5c11\u7684\u7f13\u5b58\u672a\u547d\u4e2d\u3002<\/strong><\/p>\n
    \n
    \ud83d\udd37 \u516b\u3001\u9884\u53d6\uff08Prefetching\uff09\u2014\u2014 \u4e3b\u52a8\u63d0\u793a CPU<\/h3>\n
    \n
    \n
    <\/div>\n<\/div>\n
    cpp<\/div>\n
    \n
    #include <xmmintrin.h>  \/\/ \u6216 <immintrin.h>\r\n\r\nfor (size_t i = 0; i < v.size(); i++) {\r\n    if (i + 16 < v.size()) {\r\n        __builtin_prefetch(&v[i + 16]);  \/\/ \u63d0\u524d\u544a\u8bc9CPU\uff1a\"16\u4e2a\u5143\u7d20\u540e\u4f1a\u7528\u5230\u8fd9\u5757\u5185\u5b58\"\r\n    }\r\n    process(v[i]);\r\n}<\/pre>\n
     <\/p>\n<\/div>\n<\/div>\n
    \u9002\u5408\u8bbf\u95ee\u6a21\u5f0f\u53ef\u9884\u6d4b<\/strong>\u4f46\u5355\u6b21\u5904\u7406\u8017\u65f6\u8f83\u957f<\/strong>\u7684\u573a\u666f\uff0c\u8ba9 CPU \u63d0\u524d\u628a\u6570\u636e\u52a0\u8f7d\u8fdb\u7f13\u5b58\uff0c\u63a9\u76d6\u5185\u5b58\u5ef6\u8fdf\u3002<\/p>\n
    \n
    \ud83d\udd37 \u8bbe\u8ba1\u539f\u5219\u603b\u7ed3<\/h3>\n
    \n\n\n\n\n\n\n\n\n\n\n
    \u539f\u5219<\/th>\n\u505a\u6cd5<\/th>\n<\/tr>\n<\/thead>\n
    \u6570\u636e\u8fde\u7eed\u5b58\u50a8<\/td>\n\u4f18\u5148 vector<\/code>\uff0c\u5c11\u7528 list<\/code>\/map<\/code>\uff08\u7ea2\u9ed1\u6811\u6307\u9488\u8df3\u8f6c\u591a\uff09<\/td>\n<\/tr>\n
    \u8bbf\u95ee\u6a21\u5f0f\u5339\u914d\u5e03\u5c40<\/td>\n\u6279\u91cf\u5904\u7406\u67d0\u5b57\u6bb5 \u2192 SoA\uff1b\u6574\u4f53\u5904\u7406\u5bf9\u8c61 \u2192 AoS<\/td>\n<\/tr>\n
    \u907f\u514d\u4f2a\u5171\u4eab<\/td>\n\u591a\u7ebf\u7a0b\u9ad8\u9891\u5199\u7684\u53d8\u91cf\uff0c\u6309\u7f13\u5b58\u884c\u5927\u5c0f\u5bf9\u9f50\u586b\u5145<\/td>\n<\/tr>\n
    \u7d27\u51d1\u5e03\u5c40<\/td>\n\u7ed3\u6784\u4f53\u5b57\u6bb5\u6309\u5927\u5c0f\u6392\u5e8f\uff0c\u51cf\u5c11 padding<\/td>\n<\/tr>\n
    \u51cf\u5c11\u6307\u9488\u8ffd\u9010<\/td>\n\u80fd\u7528\u6570\u7ec4\u6a21\u62df\u7684\u6811\/\u56fe\u7ed3\u6784\uff0c\u5c3d\u91cf\u7528\u6570\u7ec4<\/td>\n<\/tr>\n
    \u5c40\u90e8\u6027\u539f\u5219<\/td>\n\u628a”\u7ecf\u5e38\u4e00\u8d77\u7528”\u7684\u6570\u636e\u653e\u5f97”\u8fd1”\uff08\u65f6\u95f4\u5c40\u90e8\u6027+\u7a7a\u95f4\u5c40\u90e8\u6027\uff09<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
    \n
    \u4e00\u53e5\u8bdd\u603b\u7ed3<\/h3>\n
    \n
    Cache-friendly \u8bbe\u8ba1\u7684\u672c\u8d28\uff1a\u8ba9 CPU \u6bcf\u6b21\u52a0\u8f7d\u7f13\u5b58\u884c\u65f6\uff0c\u5c3d\u53ef\u80fd\u88c5\u6ee1”\u63a5\u4e0b\u6765\u771f\u6b63\u7528\u5f97\u5230”\u7684\u6570\u636e\uff0c\u540c\u65f6\u907f\u514d\u4e0d\u540c\u7ebf\u7a0b\u7684\u6570\u636e”\u6324\u5728\u540c\u4e00\u6761\u7f13\u5b58\u884c\u91cc\u6253\u67b6”\u3002<\/strong> \u8fd9\u5f80\u5f80\u6bd4\u5fae\u89c2\u7b97\u6cd5\u4f18\u5316\uff08\u51cf\u5c11\u51e0\u6b21\u8fd0\u7b97\uff09\u5e26\u6765\u7684\u6536\u76ca\u5927\u5f97\u591a\u2014\u2014\u56e0\u4e3a\u5185\u5b58\u5ef6\u8fdf\u624d\u662f\u73b0\u4ee3 CPU \u771f\u6b63\u7684\u74f6\u9888\u6240\u5728\u3002<\/p>\n<\/blockquote>\n
    \u60f3\u7528 Google Benchmark \u5b9e\u9645\u8dd1\u4e00\u7ec4 AoS vs SoA \u7684\u5bf9\u6bd4\u5b9e\u9a8c\uff0c\u4eb2\u773c\u770b\u770b\u6570\u5b57\u5dee\u5f02\u5417\uff1f\u6211\u53ef\u4ee5\u5e2e\u4f60\u5199\u51fa\u5b8c\u6574\u7684\u53ef\u8fd0\u884c\u4ee3\u7801\u3002<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n
    \n
    <\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n
    \n
    \n
    \n
    \n
    \n
    \n
    \n
    \n
    \n
    \n
    \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":"
    \ud83d\udd37 \u4e00\u3001\u4e3a\u4ec0\u4e48 Cache \u8fd9\u4e48\u91cd\u8981\uff1f <\/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-7438","post","type-post","status-publish","format-standard","hentry","category-value_docs"],"_links":{"self":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/7438","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=7438"}],"version-history":[{"count":1,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/7438\/revisions"}],"predecessor-version":[{"id":7439,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/7438\/revisions\/7439"}],"wp:attachment":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/media?parent=7438"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/categories?post=7438"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/tags?post=7438"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}