{"id":1688,"date":"2020-09-04T01:59:46","date_gmt":"2020-09-03T17:59:46","guid":{"rendered":"https:\/\/blog.dynox.cn\/?p=1688"},"modified":"2023-08-07T02:13:19","modified_gmt":"2023-08-06T18:13:19","slug":"cache%e4%b8%8e%e5%86%85%e5%ad%98%e7%9a%84%e6%98%a0%e5%b0%84","status":"publish","type":"post","link":"https:\/\/blog.dynox.cn\/?p=1688","title":{"rendered":"Cache\u4e0e\u5185\u5b58\u7684\u6620\u5c04"},"content":{"rendered":"<div class=\"gruber-markdown\"><h1>1. \u7406\u89e3Cache Line<\/h1>\n<p>\u5728\u5927\u5bb6\u5370\u8c61\u4e2dCache Line\u5c31\u662f\u4e00\u4e2a\u6570\u636e\u5757\uff0c\u80fd\u6709\u4ec0\u4e48\u7406\u89e3\u96be\u5ea6\u5462\uff1f\u4e0d\u59a8\u518d\u53cd\u95ee\u4e00\u4e0b\u81ea\u5df1\uff1a\u771f\u7684\u662f\u8fd9\u6837\u5417\uff1f<\/p>\n<p>\u4e0a\u7bc7\u6587\u7ae0\u4e2d\u5c31\u8bf4\u5230Cache\u672c\u8eab\u7684\u5bb9\u91cf\u8fdc\u8fdc\u5c0f\u4e8e\u5185\u5b58\u5bb9\u91cf\uff0cCPU\u4e3a\u4e86\u80fd\u6b63\u786e\u5b9a\u4f4d\u6570\u636e\u6240\u5728\u7684CacheLine\u8fd8\u9700\u8981\u505a\u5f88\u591a\u5de5\u4f5c\u3002\u7b80\u5355\u6765\u8bf4\u53ef\u4ee5\u5c06Cache Line\u7406\u89e3\u6210\u4e00\u4e2a\u5e26\u6807\u7b7e\u7684\u5b58\u50a8\u69fd\uff0c\u4e0b\u9762\u4ee5\u4e00\u4e2a\u76f4\u89c2\u7684\u4f8b\u5b50\u6765\u8bf4\u660e\uff1a<\/p>\n<p>\u5c0fA\u540c\u5b66\u5750\u5728\u5ea7\u4f4d\u4e0a\uff0c\u5982\u679c\u8001\u5e08\u60f3\u68c0\u67e5\u5c0fA\u7684\u4f5c\u4e1a\u7684\u8bdd\u5c31\u9700\u8981\u5148\u5b9a\u4f4d\u5230\u5c0fA\u6240\u5728\u7684\u5ea7\u4f4d\u53f7\uff0c\u7136\u540e\u518d\u4ece\u5c0fA\u7684\u5ea7\u4f4d\u4e0a\u62ff\u5230\u5c0fA\u4f5c\u4e1a\u672c\u3002\u5728\u8fd9\u4e2a\u4f8b\u5b50\u4e2d\uff0c\u5c0fA\u7684\u4f5c\u4e1a\u672c\u5c31\u5bf9\u5e94Cache Line\u4e2d\u7684\u6570\u636e\uff0c\u8001\u5e08\u5c31\u662fCPU Core\uff0c\u5c0fA\u5176\u5b9e\u5bf9\u5e94\u7740\u5185\u5b58\u5730\u5740\uff08TAG\uff09\uff0c\u5c0fA\u7684\u5ea7\u4f4d\u5c31\u662fCache Line\u672c\u8eab\uff0c\u800c\u5ea7\u4f4d\u53f7\u5c31\u662fCache Line\u5728Cache\u4e2d\u7684\u4f4d\u7f6e(\u7d22\u5f15\uff0cIndex)\uff0c\u6559\u5ba4\u91cc\u6240\u6709\u7684\u5ea7\u4f4d\u5c31\u53ef\u4ee5\u7406\u89e3\u4e3a\u6574\u4e2aCache\uff0c\u800c\u5b66\u6821\u91cc\u6240\u6709\u7684\u5b66\u751f\u5219\u662f\u5168\u90e8\u7684\u7cfb\u7edf\u5185\u5b58\u3002\n<img decoding=\"async\" src=\"https:\/\/\/blog.dynox.cn\/wp-content\/uploads\/2020\/09\/CPU-Cache-Flags.jpg\" alt=\"Cache Flags\" \/><\/p>\n<p>\u4e0a\u56fe\u5c31\u662fCache\u7684\u5185\u90e8\u7ec4\u7ec7\uff0c\u9664\u4e86TAG\u548c\u6570\u636e\u5916\uff0c\u8fd8\u6709\u4e24\u4e2a\u6807\u5fd7\u4f4d\uff0cV\u8868\u793a\u6b64CacheLine\u4e2d\u7684\u6570\u636e\u662f\u5426\u662f\u6709\u6548\u7684\uff0c\u5373\u5ea7\u4f4d\u4e0a\u6709\u6ca1\u6709\u5b66\u751f\uff0cD\u8868\u793aCacheLine\u4e2d\u7684\u6570\u636e\u6709\u6ca1\u6709\u88ab\u4fee\u6539\u8fc7\uff0c\u4fee\u6539\u8fc7\u7684\u6570\u636e\u662f\u4e0d\u80fd\u76f4\u63a5\u6e05\u9664\u7684\uff0c\u9700\u8981\u5199\u56de\u5230\u4e3b\u5b58\uff08\u5185\u5b58\uff09\u3002<\/p>\n<h1>2. Cache\u4e0e\u5185\u5b58\u7684\u6620\u5c04<\/h1>\n<p>\u6620\u5c04\u65b9\u5f0f\u67093\u79cd\uff1a<\/p>\n<ol>\n<li>\u76f4\u63a5\u6620\u5c04 (Direct Mapping)<\/li>\n<li>\u7ec4\u76f8\u8054 (K-Way Set Associative Mapping)<\/li>\n<li>\u5168\u76f8\u8054 (Full Associative Mapping)<\/li>\n<\/ol>\n<h2>2.1 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(MMU, Mmemory Management Unit) \u7684TLB\u7f13\u5b58 (Translation Lookaside Buffer)\uff0cTLB\u4e2d\u5b58\u653e\u7684\u662f\u865a\u62df\u5730\u5740\u4e0e\u7269\u7406\u5730\u5740\u76841:1\u7684\u8f6c\u6362\u5173\u7cfb\u3002<\/p>\n<h2>2.2 \u76f4\u63a5\u6620\u5c04<\/h2>\n<p>\u5047\u8bbe\u4e0a\u9762\u4f8b\u5b50\u4e2d\u7684\u6559\u5ba4\u53ea\u670920\u4e2a\u5ea7\u4f4d\uff0c\u7f16\u53f7\u4e3a0-19\uff0c\u5168\u6821\u5171\u6709400\u540d\u5b66\u751f\uff0c\u5b66\u53f7\u5206\u522b\u4e3a0-399\u3002\u76f4\u63a5\u6620\u5c04\u65b9\u5f0f\u7684\u6c42\u662f\u5ea7\u4f4d\u4e0d\u80fd\u968f\u4fbf\u9009\u62e9\uff0c\u800c\u662f\u901a\u8fc7\u5b66\u53f7\u548c\u6240\u6709\u5ea7\u4f4d\u6570\u7684\u4f59\u6570\u51b3\u5b9a\uff0c\u5373\u5b66\u53f7\u4e3a0\u300120\u300140\u300160...\u7684\u540c\u5b66\u53ea\u80fd\u5750\u57280\u53f7\u5ea7\u4f4d\u4e0a\uff0c\u540c\u6837\u5b66\u53f7\u4e3a1\u300121\u300141\u300161...\u7684\u540c\u5b66\u53ea\u80fd\u4e891\u53f7\u5ea7\u4f4d\uff0c\u540e\u6765\u7684\u540c\u5b66\u4f1a\u5c06\u6b63\u5750\u5728\u4f4d\u7f6e\u4e0a\u7684\u540c\u5b66\u6324\u51fa\u53bb\uff0c\u5982\u679c1\u53f7\u548c21\u53f7\u540c\u5b66\u90fd\u8981\u6765\u6559\u5ba4\u7684\u8bdd\u5c31\u4f1a\u53d1\u751f\u4e24\u4eba\u4e0d\u65ad\u88ab\u6324\u51fa\u53bb\u7684\u60c5\u51b5\uff0c\u8fd9\u5c31\u662fCache\u7684\u98a0\u7c38\u6548\u5e94\uff08Cache Thrashing\uff09\u3002<\/p>\n<h2>2.3 \u7ec4\u76f8\u8054<\/h2>\n<p>\u4e3a\u4e86\u89e3\u51b3\u76f4\u63a5\u6620\u5c04\u7684\u98a0\u7c38\u6548\u5e94\uff0c\u9042\u5f15\u5165\u4e86\u7ec4\u76f8\u8054\u6620\u5c04\u3002\u5047\u8bbe\u5b66\u6821\u5171\u67095\u4e2a\u7cfb\uff0c\u6bcf\u4e2a\u7cfb\u5747\u670980\u540d\u5b66\u751f\uff0c\u90a3\u6211\u4eec\u53ef\u4ee5\u8fd9\u6837\u5b89\u6392\u5ea7\u4f4d\uff0c\u4e00\u7cfb\u7684\u5b66\u751f\u53ea\u80fd\u9009\u62e90\/5\/10\/15\u8fd94\u4e2a\u5ea7\uff0c\u4e8c\u7cfb\u5219\u662f1\/6\/11\/16\uff0c\u4f9d\u6b21\u7c7b\u63a8\uff0c\u5982\u4e0b\u56fe\u6240\u793a\uff1a\u6bcf\u4e2a\u7cfb\u67094\u4e2a\u5ea7\u4f4d\uff0c\u8fd94\u4e2a\u5ea7\u4f4d\u662f\u6ca1\u6709\u987a\u5e8f\u7684\uff0c\u5373\u672c\u7cfb\u7684\u5b66\u751f\u968f\u610f\u5750\uff0c\u4f46\u5168\u7cfb\u768480\u540d\u5b66\u751f\u5c06\u4e89\u62a2\u8fd94\u4e2a\u5ea7\u4f4d\uff0c\u8fd9\u79cd\u5206\u4e3a5\u7ec4\u7684\u6620\u5c04\u65b9\u5f0f\u5c31\u662f4\u8def\u7ec4\u76f8\u8fde\u6620\u5c04\uff0c4\u8def\u7684\u610f\u601d\u662f\u6bcf\u7ec4\u4e2d\u67094\u4e2a\u5ea7\u4f4d\uff0c\u53734\u4e2aCacheLine\u3002\u73b0\u5b9e\u4e2dCPU Cache\u65e0\u8bba\u662f\u7ec4\u6570\u8fd8\u662f\u76f8\u8054\u5ea6\uff08\u8def\uff09\u5747\u662f2\u7684\u5e42\u6307\u6570\uff0c\u4e0d\u4f1a\u51fa\u73b0\u672c\u4f8b\u4e2d\u5947\u65705\u7684\u60c5\u5f62\u3002\n<img decoding=\"async\" src=\"https:\/\/\/blog.dynox.cn\/wp-content\/uploads\/2020\/09\/CPU-Cache-Groups.jpg\" alt=\"Cache Groups\" \/>\n\u76f4\u63a5\u6620\u5c04\u65b9\u5f0f\u5176\u5b9e\u662f\u7ec4\u76f8\u8054\u6620\u5c04\u7684\u4e00\u79cd\u7279\u4f8b\uff0c\u4ea6\u79f0\u4f5c\u662f\u5355\u8def\u7ec4\u76f8\u8054\u3002<\/p>\n<h2>2.4 \u7279\u522b\u8bf4\u660e<\/h2>\n<p>\u66f4\u8be6\u7ec6\u7684\u9610\u8ff0\u53ef\u53c2\u8003\u94fe\u63a51 [\u8717\u7a9d\u79d1\u6280: \u6d45\u8c08Cache Memory]\uff0c\u4f5c\u8005smcdef\u901a\u8fc7\u4e3e\u4f8b\u6765\u8bf4\u660e\u4e09\u79cd\u65b9\u5f0f\u7684\u5b9e\u73b0\u7ec6\u8282\uff0c\u4f5c\u56fe\u7cbe\u7f8e\uff0c\u672c\u6587\u4e0d\u518d\u505a\u8fc7\u591a\u8bf4\u660e\u3002<\/p>\n<h1>3. Cache\u7684\u5206\u7c7b\u53ca\u8bbf\u95ee\u6d41\u7a0b<\/h1>\n<p>\u76ee\u524d\u4e3b\u6d41\u7684CPU\uff0c\u5982Intel\u53caAMD\u7684\u684c\u9762\u6216\u670d\u52a1\u5668\u5e73\u53f0\u7684CPU\u90fd\u662f\u652f\u6301\u5206\u9875\u7684\uff0c\u5373\u7269\u7406\u5185\u5b58\u7684\u7ba1\u7406\u662f\u4ee5\u9875\u5212\u5206\u548c\u7ba1\u7406\u7684\u3002X86\u5e73\u53f0\u7684\u9875\u5927\u5c0f\u901a\u5e38\u662f4K\uff0c\u53734096\u5b57\u8282\u3002CPU\u5c42\u6240\u64cd\u4f5c\u7684\u5185\u5b58\u5730\u5740\u79f0\u4f5c\u662f\u865a\u62df\u5730\u5740\uff08\u903b\u8f91\u5730\u5740\uff09\uff0c\u5e76\u4e0d\u662f\u7269\u7406\u7684\u5185\u5b58\u5730\u5740\uff0c\u4ece\u865a\u62df\u5730\u5740\u81f3\u7269\u7406\u5730\u5740\u7684\u7ffb\u8bd1\u7531\u786c\u4ef6MMU\u6765\u6267\u884c\u3002Cache\u4e0eMMU\u7684\u4f4d\u7f6e\u5173\u7cfb\u76f4\u63a5\u51b3\u5b9a\u4e86Cache\u7684\u5206\u7c7b\uff1a\u5982\u679cCache\u76f8\u5bf9MMU\u79bbCORE\u7684\u8ddd\u79bb\u66f4\u8fd1\uff0c\u5219\u6b64\u7c7bCache\u88ab\u79f0\u4f5c\u4e3a\u903b\u8f91Cache\uff1b\u76f8\u53cd\u5219\u79f0\u4f5c\u662f\u7269\u7406Cache\u3002\u4e0b\u56fe\u662fL1\u3001L2\u53caLLC\u4e0eMMU\u7684\u5173\u7cfb\uff0cL1\u662f\u96c6\u6210\u5728CORE\u5185\u90e8\u7684\uff0c\u6240\u4ee5\u53ef\u4ee5\u5f97\u51faL1\u662f\u903b\u8f91Cache\uff0c\u800cL2\u548cLLC\u5219\u662f\u7269\u7406Cache\u3002<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/\/blog.dynox.cn\/wp-content\/uploads\/2020\/09\/CPU-Memory-VA2PA.jpg\" alt=\"Memory Paging & Addressing\" \/><\/p>\n<p>\u5982\u679c\u518d\u52a0\u4e0aTAG\u7684\u53d6\u503c\uff0c\u53d6\u7269\u7406\u5730\u5740\u6216\u865a\u62df\u5730\u5740\uff0c\u53c8\u53ef\u4ee5\u7ec4\u5408\u62104\u79cd\u60c5\u51b5\uff1a<\/p>\n<h2>3.1. PIPT (Physically Indexed Virtually Tagged\uff09<\/h2>\n<p>\u4e0b\u56fe\u662f2\u8def\u7ec4\u76f8\u8054\u7684PIPT\u7684\u793a\u4f8b\uff0cCacheLine\u5927\u5c0f\u4e3a64\u5b57\u8282\uff0c\u53736\u4e2a\u6bd4\u7279\uff0c\u7ec4\u7d22\u5f15\uff08SET\uff09\u7531S\u4e2a\u6bd4\u7279\u6765\u7f16\u5740\uff0c\u5269\u4f59\u7684\u90e8\u5206\u5373\u4e3a\u6807\u7b7e\u9879\uff08TAG\uff09\uff0cCPU\u901a\u8fc7\u7ec4\u7d22\u5f15\u6765\u5b9a\u4f4d\u6b64\u5730\u5740\u6240\u5728Cache\u7ec4\uff0c\u7136\u540e\u901a\u8fc7\u4e24\u7ec4\u6bd4\u8f83\u7535\u8def\u8fdb\u884cTAG\u503c\u7684\u5e76\u53d1\u6bd4\u8f83\uff0c\u7136\u540e\u5373\u53ef\u786e\u5b9aCache\u6240\u5728\u4f4d\u7f6e\uff0c\u5f53\u7136\u4e5f\u6709\u53ef\u80fd\u51fa\u73b0\u6ca1\u6709\u547d\u4e2d\u7684\u60c5\u51b5\u3002\n<img decoding=\"async\" src=\"https:\/\/\/blog.dynox.cn\/wp-content\/uploads\/2020\/09\/CPU-Cache-PIPT.jpg\" alt=\"Cache PIPT}\" \/>\nL2\u53caLLC\uff0c\u4ee5\u53ca\u65e9\u671f\u7684CPU\u7684L1\u5747\u662f\u4f7f\u7528PIPT\u7684\u65b9\u5f0f\uff0c\u8fd9\u662f\u56e0\u4e3a\u5185\u5b58\u7684\u7269\u7406\u5730\u5740\u662f\u552f\u4e00\u7684\uff0c\u8fd9\u5c31\u5927\u5927\u7b80\u5355\u5316PIPT\u7684\u5b9e\u73b0\u903b\u8f91\u3002<\/p>\n<h2>3.2. VIVT (Virtually Indexed Virtually Tagged\uff09<\/h2>\n<p>VIVT\u7684Index\u548cTag\u5747\u4f7f\u7528\u865a\u62df\u5730\u5740\uff0c\u5168\u7a0b\u4e0d\u9700\u8981MMU\u7684\u53c2\u4e0e\uff0c\u662f\u6027\u80fd\u6700\u597d\u7684\u5b9a\u4f4d\u65b9\u5f0f\uff0c\u4f46\u662f\u7531\u4e8e\u865a\u62df\u5730\u5740\u7684\u7279\u6027\u4f1a\u5bfc\u81f4\u6b67\u4e49\u548c\u522b\u540d\u7684\u95ee\u9898\uff0c\u6700\u7ec8\u51b3\u5b9a\u4e86VIVT\u65b9\u5f0f\u7684\u4e0d\u53ef\u884c\uff1a<\/p>\n<p>\u6b67\u4e49 (Ambiguity\uff0c\u4ea6\u79f0Homonyms\u95ee\u9898)\uff1a\u4e0d\u540c\u7684\u8fdb\u7a0b\u62e5\u6709\u76f8\u540c\u7684\u865a\u62df\u5730\u5740\u7a7a\u95f4\uff0c\u865a\u62df\u5316\u5e73\u53f0\u4e0a\u4e0d\u540c\u7684\u865a\u62df\u673a\u4ea6\u662f\u540c\u6837\u7684\u60c5\u51b5\u3002\u4ece\u800c\u4f1a\u5bfc\u81f4\u76f8\u540c\u7684\u865a\u62df\u5730\u5740\uff08\u4e0d\u540c\u8fdb\u7a0b\u6216\u4e0d\u540c\u865a\u62df\u673a\uff09\u6240\u5bf9\u5e94\u7684\u7269\u7406\u9875\u9762\u4e0d\u540c\u7684\uff0cVIVT\u7684\u65b9\u5f0f\u5c06\u4e0d\u80fd\u6b63\u786e\u533a\u5206\u3002<\/p>\n<p>\u522b\u540d (Alias)\uff1a\u662f\u6307\u540c\u4e00\u4e2a\u7269\u7406\u9875\u6620\u5c04\u81f3\u4e0d\u540c\u7684\u865a\u62df\u5730\u5740\uff0c\u5373\u540c\u4e00\u4e2a\u7269\u7406\u5730\u5740\u5c06\u6709\u591a\u4e2a\u865a\u62df\u5730\u5740\u7684\u522b\u540d\u3002\u591a\u4e2a\u522b\u540d\u7684\u60c5\u51b5\u4e0bVIVT\u5c06\u4f1a\u6620\u5c04\u81f3\u4e0d\u540c\u7684CacheLine\uff0c\u5c06\u4e0d\u80fd\u4fdd\u8bc1\u6570\u636e\u7684\u4e00\u81f4\u6027\u3002<\/p>\n<h2>3.3. VIPT (Virtually Indexed Physically Tagged\uff09<\/h2>\n<p>CPU\u5c42\u7684\u6307\u4ee4\u6240\u64cd\u4f5c\u7684\u5747\u662f\u865a\u62df\u5730\u5740\uff0c\u4f7f\u7528\u865a\u62df\u5730\u5740\u4f5c\u4e3a\u7d22\u5f15\u6765\u76f4\u63a5\u8fdb\u884cCache\u7684\u5b9a\u4f4d\u4e0d\u5fc5\u7ecf\u8fc7MMU\u7684\u8f6c\u6362\u3002\u6b64\u65f6Cache Set\u7684\u5b9a\u4f4d\u548cMMU\u7684\u8f6c\u6362\u8fc7\u7a0b\u662f\u5e76\u53d1\u7684\uff0c\u5b9a\u4f4d\u5230\u6307\u5b9aCache Set\u4e4b\u540e\u518d\u8fdb\u884c\u4e24\u4e2aCache Line\u7684Tag\u7684\u5bf9\u6bd4\uff0c\u6b64\u65f6\u4e24\u4e2aTag\u7684\u6bd4\u5bf9\u4e5f\u662f\u5e76\u884c\u5904\u7406\u7684\u3002\n<img decoding=\"async\" src=\"https:\/\/\/blog.dynox.cn\/wp-content\/uploads\/2020\/09\/CPU-Cache-VIPT.jpg\" alt=\"Cache VIPT}\" \/><\/p>\n<h2>3.4. PIVT (Physically Indexed Virtually Tagged\uff09<\/h2>\n<p>PIVT\u65b9\u5f0f\u76f8\u6bd4PIPT\u548cVIPT\u6765\u8bf4\u6ca1\u6709\u4efb\u4f55\u4f18\u52bf\uff0c\u6027\u80fd\u4e0a\u5fc5\u987b\u7b49MMU\u8f6c\u6362\u5b8c\u6210\u4e4b\u540e\uff0c\u800c\u4e14\u5728\u6570\u636e\u4e00\u81f4\u6027\u4e0a\u65e0\u6cd5\u5904\u7406\u597d\u522b\u540d\u95ee\u9898\u3002<\/p>\n<h1>4. L1 Cache (VIPT)\u7684\u522b\u540d\u95ee\u9898<\/h1>\n<p>\u5728Cache\u4e0e\u5185\u5b58\u7684\u6620\u5c04\u5173\u7cfb\u4e0a\uff0c\u8003\u8651\u5230\u6210\u672c\u53ca\u6027\u80fd\uff0c\u591a\u91c7\u7528\u7ec4\u76f8\u8054\u65b9\u5f0f\uff1b\u5728CacheLine\u7684\u5b9a\u4f4d\u548c\u8bbf\u95ee\u65b9\u5f0f\u4e0a\uff0cL1 Cache\u591a\u662fVIPT\uff0c\u800cL2\u53caLLC\u662fPIPT\u3002\u4ee5Intel Pentinum G5500T\u4e3a\u4f8b\uff1aL1\u662f8\u8def\u7ec4\u76f8\u8054\uff0c\u5927\u5c0f\u4e3a32K; L2\u662f4\u8def\u7ec4\u76f8\u8054\uff0c\u5927\u5c0f\u4e3a256K;LLC\u5373L3\u5219\u662f16\u8def\u7ec4\u76f8\u8054\uff0c\u5927\u5c0f\u4e3a4M\u3002<\/p>\n<p>L1\u91c7\u7528\u7684\u662fVIPT\u6620\u5c04\u65b9\u5f0f\uff0c\u867d\u7136VIPT\u65b9\u5f0f\u901a\u8fc7\u7269\u7406\u5730\u5740TAG\u89e3\u51b3\u4e86\u6b67\u4e49\u7684\u95ee\u9898\uff0c\u4f46\u522b\u540d\u7684\u95ee\u9898\u4f9d\u7136\u5b58\u5728\uff0c\u662f\u600e\u6837\u89e3\u51b3\u7684\u5462\uff1f<\/p>\n<p>\u5b9e\u9645\u4e0aL1 Cache\u7684\u6bcf\u4e2aCache Set\u7684\u6570\u91cf\u6b63\u597d\u9650\u5b9a\u5728 (PAGE_SIZE\/CACHE_LINE) \u4e4b\u5185\u7684\uff0c\u4ee5G5500T\u4e3a\u4f8b\uff0c32K\/(8*64) = 4K\/64 = 64\u3002\u865a\u62df\u5730\u5740\u6700\u4f4e6\u4f4d\u4e3aCacheLine\u4e2d\u7684\u504f\u79fb\uff1b\u4f4d6-11\u51716\u4f4d\u662f\u7ec4\u7d22\u5f15\uff0c6+6\u6b63\u597d\u662f12\uff0c\u5373\u4e00\u4e2a4K PAGE\u7684\u5927\u5c0f\uff0c\u4ece\u800c\u53ef\u63a8\u8bba\u51fa\u4e0d\u7ba1\u865a\u62df\u5730\u5740\u662f\u591a\u5c11\uff0c\u4efb\u610f\u5185\u5b58\u9875\u9762\u7684\u56fa\u5b9a\u504f\u79fb\u603b\u662f\u6620\u5c04\u5230\u76f8\u540c\u7684Cache Set\u4e2d\uff0c\u800cTAG\u7684\u9009\u62e9\u6b63\u662f\u7269\u7406\u5730\u5740\u4e2d\u7684\u662f12-47\uff0c\u53ef\u4ee5\u7406\u89e3\u4e3aPFN\uff0c\u5373\u6bcf\u4e00\u4e2a\u7269\u7406\u9875\u9762\u7684\u552f\u4e00\u5e27\u53f7\uff0c\u6240\u4ee5\u540c\u4e00\u7269\u7406\u9875\u7684\u4e0d\u540c\u7684\u865a\u62df\u5730\u5740\u6700\u7ec8\u5c06\u5b9a\u4f4d\u5230\u540c\u4e00\u4e2aCache Set\u4e2d\u7684\u540c\u4e00\u4e2aCache Line\u4e0a\u3002<\/p>\n<p>L1\u662f8\u8def\u7ec4\u76f8\u8054\u7684\uff0c\u4e5f\u5c31\u662f\u8bf4\u4e00\u4e2aCache Set\u4e2d\u5bb9\u7eb3\u4e868\u4e2aCache Line\uff0c\u7531\u4e0a\u9762\u7684\u7ed3\u8bba\u53ef\u5f97\u51fa\uff1a\u8fd98\u4e2aCache Line\u5c06\u5206\u522b\u6765\u81ea\u4e8e\u4e0d\u540c\u7684\u7269\u7406\u9875\u3002\u6700\u540e\u5927\u5bb6\u4e0d\u59a8\u60f3\u4e00\u4e2a\u95ee\u9898\uff0c\u5982\u679c\u8981\u5c06L1 Cache\u4ece32K\u589e\u52a0\u523064K\u7684\u8bdd\uff0c\u600e\u6837\u6784\u9020L1\u7684\u76f8\u8054\u5ea6\u53caCache Set\u7ec4\u6570\u624d\u662f\u5408\u7406\u7684\uff1f\u6709\u591a\u5c11\u79cd\u7ec4\u5408\uff1f<\/p>\n<h1>5. \u53c2\u8003\u8fde\u63a5<\/h1>\n<ul>\n<li><a href=\"http:\/\/www.wowotech.net\/memory_management\/458.html\"> \u6d45\u8c08Cache Memory<\/a><\/li>\n<li><a href=\"https:\/\/chipressco.wpcomstaging.com\/2019\/04\/07\/what-are-the-types-of-caches-based-on-index-and-tag-bits\/\">What are the types of caches based on index and tag bits?<\/a><\/li>\n<\/ul><\/div>","protected":false},"excerpt":{"rendered":"<p>1. \u7406\u89e3Cache Line \u5728\u5927\u5bb6\u5370\u8c61\u4e2dCache Line\u5c31\u662f\u4e00\u4e2a\u6570\u636e\u5757\uff0c\u80fd\u6709\u4ec0\u4e48\u7406\u89e3\u96be\u5ea6\u5462\uff1f\u4e0d\u59a8\u518d\u53cd\u95ee [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"footnotes":""},"categories":[1],"tags":[626,622,631,632,634,630,633],"views":814,"_links":{"self":[{"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=\/wp\/v2\/posts\/1688"}],"collection":[{"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1688"}],"version-history":[{"count":1,"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=\/wp\/v2\/posts\/1688\/revisions"}],"predecessor-version":[{"id":1690,"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=\/wp\/v2\/posts\/1688\/revisions\/1690"}],"wp:attachment":[{"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1688"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1688"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1688"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}