{"id":4039,"date":"2024-05-01T09:00:31","date_gmt":"2024-05-01T01:00:31","guid":{"rendered":"https:\/\/xinchewhd.com.cn\/index.php\/%e9%9d%a2%e8%af%95\/%e9%9d%a2%e8%af%95%e5%ae%98%ef%bc%9a%e4%b8%8e%e4%bd%bf%e7%94%a8%e9%94%81%e7%9b%b8%e6%af%94%ef%bc%8ccas-%e6%93%8d%e4%bd%9c%e7%9a%84%e6%80%a7%e8%83%bd%e4%bc%98%e5%8a%bf%e5%92%8c%e5%8a%a3%e5%8a%bf\/"},"modified":"2024-05-01T09:00:31","modified_gmt":"2024-05-01T01:00:31","slug":"%e9%9d%a2%e8%af%95%e5%ae%98%ef%bc%9a%e4%b8%8e%e4%bd%bf%e7%94%a8%e9%94%81%e7%9b%b8%e6%af%94%ef%bc%8ccas-%e6%93%8d%e4%bd%9c%e7%9a%84%e6%80%a7%e8%83%bd%e4%bc%98%e5%8a%bf%e5%92%8c%e5%8a%a3%e5%8a%bf","status":"publish","type":"post","link":"https:\/\/xinchewhd.com.cn\/index.php\/%e9%9d%a2%e8%af%95\/%e9%9d%a2%e8%af%95%e5%ae%98%ef%bc%9a%e4%b8%8e%e4%bd%bf%e7%94%a8%e9%94%81%e7%9b%b8%e6%af%94%ef%bc%8ccas-%e6%93%8d%e4%bd%9c%e7%9a%84%e6%80%a7%e8%83%bd%e4%bc%98%e5%8a%bf%e5%92%8c%e5%8a%a3%e5%8a%bf\/","title":{"rendered":"\u9762\u8bd5\u5b98\uff1a\u4e0e\u4f7f\u7528\u9501\u76f8\u6bd4\uff0cCAS \u64cd\u4f5c\u7684\u6027\u80fd\u4f18\u52bf\u548c\u52a3\u52bf\u6709\u54ea\u4e9b\uff1f"},"content":{"rendered":"
\n

1\u3001\u4ec0\u4e48\u662fCAS\uff08Compare-And-Swap\uff09<\/strong><\/span><\/p>\n

CAS\uff08Compare-And-Swap\uff09\u662f\u4e00\u79cd\u65e0\u9501\u7f16\u7a0b\u6280\u672f\uff0c\u5b83\u7684\u5b9e\u73b0\u6b65\u9aa4\u5982\u4e0b\uff1a<\/span><\/p>\n

    \n
  1. \n

    \u6bd4\u8f83<\/span><\/strong>\uff1a\u5b83\u5c06\u5185\u5b58\u4f4d\u7f6e\u7684\u5f53\u524d\u503c\u4e0e\u7ed9\u5b9a\u7684\u671f\u671b\u503c\u8fdb\u884c\u6bd4\u8f83\u3002<\/span><\/p>\n<\/li>\n

  2. \n

    \u4ea4\u6362<\/span><\/strong>\uff1a\u53ea\u6709\u5f53\u5f53\u524d\u503c\u4e0e\u671f\u671b\u503c\u76f8\u540c\u65f6\uff0c\u5b83\u624d\u5c06\u8be5\u5185\u5b58\u4f4d\u7f6e\u4e0a\u7684\u503c\u66ff\u6362\u4e3a\u65b0\u7684\u7ed9\u5b9a\u503c\u3002<\/span><\/p>\n<\/li>\n<\/ol>\n

    \u8fd9\u4e2a\u8fc7\u7a0b\u662f\u539f\u5b50\u7684\uff0c<\/strong>\u610f\u5473\u7740\u5728\u6574\u4e2a\u6bd4\u8f83\u5e76\u4ea4\u6362\u7684\u8fc7\u7a0b\u4e2d\uff0c\u5176\u4ed6\u7ebf\u7a0b\u4e0d\u80fd\u4ecb\u5165\u4fee\u6539\u5185\u5b58\u4f4d\u7f6e\u7684\u503c\u3002\u5982\u679c\u5f53\u524d\u503c\u4e0e\u671f\u671b\u503c\u4e0d\u5339\u914d\uff0c\u90a3\u4e48\u64cd\u4f5c\u5931\u8d25\uff0c\u5185\u5b58\u4f4d\u7f6e\u7684\u503c\u4e0d\u4f1a\u6539\u53d8\u3002<\/span><\/section>\n
    \u5728\u4f2a\u4ee3\u7801\u4e2d\uff0cCAS \u53ef\u4ee5\u8868\u793a\u5982\u4e0b\uff1a<\/span><\/span><\/section>\n
    \n
      \n
    • <\/li>\n
    • <\/li>\n
    • <\/li>\n
    • <\/li>\n
    • <\/li>\n
    • <\/li>\n<\/ul>\n
      function CAS(memory_location, expected_value, new_value):<\/span><\/code>    if<\/span> *memory_location == expected_value:<\/span><\/code>        *memory_location = new_value<\/span><\/code>        return<\/span> true<\/span><\/span><\/code>    else<\/span>:<\/span><\/code>        return<\/span> false<\/span><\/span><\/code><\/pre>\n<\/section>\n
      CAS \u901a\u5e38\u7531\u73b0\u4ee3\u5904\u7406\u5668\u76f4\u63a5\u652f\u6301\uff0c\u5e76\u53ef\u901a\u8fc7\u4e00\u4e9b\u9ad8\u7ea7\u7f16\u7a0b\u8bed\u8a00\u7684\u539f\u5b50\u5e93\u6216\u8005\u5185\u5efa\u51fd\u6570\u6765\u8bbf\u95ee\u3002\u5b83\u662f\u6784\u5efa\u66f4\u590d\u6742\u65e0\u9501\u7b97\u6cd5\u7684\u6784\u4ef6\u5757\uff0c\u56e0\u4e3a\u5b83\u53ef\u4ee5\u4fdd\u8bc1\u5373\u4f7f\u5728\u6709\u591a\u4e2a\u7ebf\u7a0b\u5c1d\u8bd5\u540c\u65f6\u66f4\u65b0\u540c\u4e00\u4e2a\u53d8\u91cf\u7684\u60c5\u51b5\u4e0b\uff0c\u53d8\u91cf\u7684\u66f4\u65b0\u4e5f\u53ef\u4ee5\u5b89\u5168\u5730\u8fdb\u884c\u3002<\/span><\/h3>\n
      2\u3001CAS\u7684\u6027\u80fd\u4f18\u52bf<\/strong><\/span><\/h3>\n
        \n
      1. \n
        \u975e\u963b\u585e\u7279\u6027<\/span><\/strong>\uff1aCAS \u64cd\u4f5c\u901a\u5e38\u662f\u975e\u963b\u585e\u7684\uff0c\u56e0\u6b64\u7ebf\u7a0b\u4e0d\u4f1a\u5728\u7b49\u5f85\u8d44\u6e90\u65f6\u88ab\u6302\u8d77\uff0c\u51cf\u5c11\u4e86\u4e0a\u4e0b\u6587\u5207\u6362\u548c\u8c03\u5ea6\u5ef6\u8fdf\u3002<\/span><\/p>\n<\/li>\n
      2. \n
        \u7f29\u77ed\u540c\u6b65\u65f6\u95f4\u6bb5<\/span><\/strong>\uff1aCAS \u4ec5\u5728\u5b9e\u9645\u66f4\u65b0\u6570\u636e\u65f6\u9700\u8981\u540c\u6b65\uff0c\u53ef\u4ee5\u7f29\u77ed\u4ee3\u7801\u4e2d\u53d7\u4fdd\u62a4\u533a\u57df\u7684\u957f\u5ea6\u3002<\/span><\/p>\n<\/li>\n
      3. \n
        \u907f\u514d\u6b7b\u9501<\/span><\/strong>\uff1a\u7531\u4e8e\u6ca1\u6709\u9501\u7684\u6982\u5ff5\uff0cCAS \u64cd\u4f5c\u4e0d\u4f1a\u4ea7\u751f\u6b7b\u9501\u95ee\u9898\u3002<\/span><\/p>\n<\/li>\n
      4. \n
        \u53ef\u6269\u5c55\u6027<\/span><\/strong>\uff1a\u5728\u591a\u6838\u5904\u7406\u5668\u4e0a\uff0cCAS \u53ef\u4ee5\u66f4\u597d\u5730\u6269\u5c55\uff0c\u5728\u7406\u60f3\u60c5\u51b5\u4e0b\uff0c\u6bcf\u4e2a\u6838\u5fc3\u53ef\u4ee5\u72ec\u7acb\u8fdb\u884c\u8ba1\u7b97\u800c\u4e0d\u4f1a\u4e92\u76f8\u5f71\u54cd\u3002<\/span><\/p>\n<\/li>\n<\/ol>\n
        3\u3001CAS\u7684\u6027\u80fd\u52a3\u52bf<\/strong><\/span><\/h3>\n
          \n
        1. \n
          \u5fd9\u7b49\u5f85<\/span><\/strong>\uff1a\u5982\u679c\u591a\u4e2a\u7ebf\u7a0b\u540c\u65f6\u5c1d\u8bd5\u8fdb\u884c CAS \u64cd\u4f5c\uff0c\u5b83\u4eec\u53ef\u80fd\u4f1a\u8fdb\u5165\u4e00\u4e2a\u5fd9\u7b49\uff08spin-wait\uff09\u5faa\u73af\uff0c\u8fd9\u4f1a\u6d6a\u8d39CPU\u8d44\u6e90\u3002<\/span><\/p>\n<\/li>\n
        2. \n
          ABA\u95ee\u9898<\/span><\/strong>\uff1a\u5982\u679c\u4e00\u4e2a\u53d8\u91cf\u4ece A \u4fee\u6539\u4e3a B\uff0c\u7136\u540e\u53c8\u88ab\u6539\u56de A\uff0c\u4f7f\u7528 CAS \u7684\u7ebf\u7a0b\u53ef\u80fd\u4f1a\u9519\u8bef\u5730\u8ba4\u4e3a\u6ca1\u6709\u5176\u4ed6\u7ebf\u7a0b\u4fee\u6539\u8fc7\u8be5\u53d8\u91cf\u3002<\/span><\/p>\n<\/li>\n
        3. \n
          \u9650\u5236\u7684\u9002\u7528\u6027<\/span><\/strong>\uff1aCAS \u66f4\u9002\u5408\u7b80\u5355\u7684\u539f\u5b50\u64cd\u4f5c\uff0c\u5e76\u4e0d\u5bb9\u6613\u76f4\u63a5\u5e94\u7528\u5230\u590d\u6742\u7684\u6570\u636e\u7ed3\u6784\u64cd\u4f5c\u4e2d\u3002<\/span><\/p>\n<\/li>\n
        4. \n
          \u5f00\u53d1\u96be\u5ea6<\/span><\/strong>\uff1a\u5b9e\u73b0\u6b63\u786e\u7684\u65e0\u9501\u6570\u636e\u7ed3\u6784\u6bd4\u4f7f\u7528\u9501\u8981\u56f0\u96be\u5f97\u591a\uff0c\u9700\u8981\u66f4\u6df1\u5165\u7684\u7406\u89e3\u5e76\u53d1\u63a7\u5236\u7684\u7ec6\u8282\u3002<\/span><\/p>\n<\/li>\n<\/ol>\n
          4\u3001\u5982\u4f55\u9009\u62e9<\/strong><\/span><\/h3>\n
          \u9009\u62e9CAS\u8fd8\u662f\u9501\uff0c\u53d6\u51b3\u4e8e\u4ee5\u4e0b\u56e0\u7d20\uff1a<\/span><\/p>\n
            \n
          1. \n
            \u7ade\u4e89\u7a0b\u5ea6<\/span><\/strong>\uff1a\u5f53\u7cfb\u7edf\u4e2d\u7684\u7ebf\u7a0b\u7ade\u4e89\u4e0d\u6fc0\u70c8\u65f6\uff0cCAS \u53ef\u4ee5\u63d0\u4f9b\u975e\u5e38\u597d\u7684\u6027\u80fd\u3002\u4f46\u5982\u679c\u7ade\u4e89\u975e\u5e38\u6fc0\u70c8\uff0c\u9891\u7e41\u5931\u8d25\u7684 CAS \u64cd\u4f5c\u53ef\u80fd\u5bfc\u81f4\u6027\u80fd\u4e0b\u964d\uff0c\u6b64\u65f6\u53ef\u80fd\u4f7f\u7528\u9501\u66f4\u5408\u9002\u3002<\/span><\/p>\n<\/li>\n
          2. \n
            \u64cd\u4f5c\u590d\u6742\u5ea6<\/span><\/strong>\uff1a\u5bf9\u4e8e\u590d\u6742\u7684\u6570\u636e\u7ed3\u6784\u6216\u8005\u64cd\u4f5c\uff0c\u7ef4\u62a4\u65e0\u9501\u7b97\u6cd5\u7684\u590d\u6742\u6027\u548c\u6b63\u786e\u6027\u53ef\u80fd\u4f1a\u5f88\u9ad8\u3002\u6b64\u65f6\u4f7f\u7528\u9501\u53ef\u80fd\u66f4\u5b89\u5168\u3001\u66f4\u4fbf\u4e8e\u7ba1\u7406\u3002<\/span><\/p>\n<\/li>\n
          3. \n
            \u5bf9\u6027\u80fd\u7684\u8981\u6c42<\/span><\/strong>\uff1a\u5982\u679c\u5e94\u7528\u7a0b\u5e8f\u5bf9\u6027\u80fd\u8981\u6c42\u6781\u9ad8\uff0c\u5e76\u4e14\u7ebf\u7a0b\u7ade\u4e89\u4e0d\u662f\u7279\u522b\u6fc0\u70c8\uff0cCAS \u53ef\u80fd\u662f\u66f4\u597d\u7684\u9009\u62e9\uff0c\u56e0\u4e3a\u5b83\u51cf\u5c11\u4e86\u4e0a\u4e0b\u6587\u5207\u6362\u7684\u5f00\u9500\u548c\u6f5c\u5728\u7684\u9501\u4e89\u7528\u3002<\/span><\/p>\n<\/li>\n
          4. \n
            \u5f00\u53d1\u548c\u7ef4\u62a4\u6210\u672c<\/span><\/strong>\uff1a\u4f7f\u7528\u9501\u901a\u5e38\u66f4\u7b80\u5355\uff0c\u6613\u4e8e\u5b9e\u73b0\u548c\u7406\u89e3\u3002\u5982\u679c\u5f00\u53d1\u65f6\u95f4\u6709\u9650\u6216\u8005\u5f00\u53d1\u8005\u5bf9\u5e76\u53d1\u63a7\u5236\u4e0d\u591f\u719f\u6089\uff0c\u90a3\u4e48\u91c7\u7528\u9501\u53ef\u80fd\u66f4\u52a0\u5b9e\u9645\u3002<\/span><\/p>\n<\/li>\n
          5. \n
            \u786c\u4ef6\u652f\u6301<\/span><\/strong>\uff1a\u73b0\u4ee3\u5904\u7406\u5668\u901a\u5e38\u90fd\u5bf9CAS\u7c7b\u64cd\u4f5c\u63d0\u4f9b\u4e86\u4f18\u5316\uff0c\u4f46\u5728\u67d0\u4e9b\u786c\u4ef6\u5e73\u53f0\u4e0a\uff0cCAS\u64cd\u4f5c\u53ef\u80fd\u4e0d\u5982\u9884\u671f\u90a3\u6837\u9ad8\u6548\u3002<\/span><\/p>\n<\/li>\n<\/ol>\n
            \u603b\u7684\u6765\u8bf4\uff0c\u6ca1\u6709\u4e00\u79cd\u540c\u6b65\u673a\u5236\u80fd\u5728\u6240\u6709\u60c5\u51b5\u4e0b\u90fd\u662f\u6700\u4f18\u7684\u3002\u8bbe\u8ba1\u51b3\u7b56\u5e94\u8be5\u57fa\u4e8e\u5177\u4f53\u7684\u5e94\u7528\u573a\u666f\u3001\u9884\u671f\u7684\u8d1f\u8f7d\u3001\u7cfb\u7edf\u67b6\u6784\u4ee5\u53ca\u7ef4\u62a4\u7684\u590d\u6742\u5ea6\u7b49\u591a\u4e2a\u56e0\u7d20\u3002\u901a\u5e38\uff0c\u5728\u521d\u671f\u5f00\u53d1\u9636\u6bb5\uff0c\u4f7f\u7528\u9501\u53ef\u80fd\u4f1a\u66f4\u7b80\u5355\uff0c\u968f\u7740\u7cfb\u7edf\u7684\u6210\u719f\u548c\u6027\u80fd\u9700\u6c42\u7684\u589e\u957f\uff0c\u518d\u8003\u8651\u8fc1\u79fb\u5230\u57fa\u4e8eCAS\u7684\u5b9e\u73b0\u3002<\/span><\/p>\n
            <\/mp-style-type><\/p>\n
            \n
            \u672c\u7bc7\u6587\u7ae0\u6765\u6e90\u4e8e\u5fae\u4fe1\u516c\u4f17\u53f7:                 \u4e92\u8054\u7f51\u9762\u8bd5\u5c0f\u5e2e\u624b              <\/p>\n<\/blockquote>\n<\/div>\n","raw":"","protected":false},"excerpt":{"rendered":"
            1\u3001\u4ec0\u4e48\u662fCAS\uff08Compare-And-Swap\uff09 CAS\uff08Compare-And-Swap\uff09\u662f\u4e00\u79cd\u65e0\u9501\u7f16\u7a0b\u6280\u672f\uff0c\u5b83\u7684\u5b9e\u73b0\u6b65\u9aa4\u5982 …<\/p>\n","protected":false},"author":1,"featured_media":4036,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"emotion":"","emotion_color":"","title_style":"","license":"","footnotes":""},"categories":[30],"tags":[],"class_list":["post-4039","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-30"],"post_thumbnail_image":"https:\/\/wp-moto-1258805347.cos.ap-shanghai.myqcloud.com\/2024\/05\/20240524144653435-150x150.jpeg","content_first_image":null,"post_medium_image_300":"https:\/\/wp-moto-1258805347.cos.ap-shanghai.myqcloud.com\/2024\/05\/20240524144653435-300x128.jpeg","post_thumbnail_image_624":"https:\/\/wp-moto-1258805347.cos.ap-shanghai.myqcloud.com\/2024\/05\/20240524144653435-1024x436.jpeg","post_frist_image":null,"post_medium_image":"https:\/\/wp-moto-1258805347.cos.ap-shanghai.myqcloud.com\/2024\/05\/20240524144653435-300x128.jpeg","post_large_image":"https:\/\/wp-moto-1258805347.cos.ap-shanghai.myqcloud.com\/2024\/05\/20240524144653435-1024x436.jpeg","post_full_image":"https:\/\/wp-moto-1258805347.cos.ap-shanghai.myqcloud.com\/2024\/05\/20240524144653435.jpeg","post_all_images":[],"videoAdId":"","listAd":"0","listAdId":"","listAdEvery":6,"total_comments":0,"category_name":"\u9762\u8bd5","post_date":"2024-05-01","like_count":"0","praiseWord":"\u9f13\u52b1","copyright_state":"","excitationAd":"0","rewardedVideoAdId":"","detailAdId":"","detailAd":"0","enterpriseMinapp":"0","audios":[],"postImageUrl":"https:\/\/wp-moto-1258805347.cos.ap-shanghai.myqcloud.com\/2023\/05\/20230519082947553.jpg","avatarurls":[],"related_posts":null,"pageviews":298,"next_post_id":4035,"next_post_title":"\u9762\u8bd5\u5b98\uff1a\u4ec0\u4e48\u662f\u751f\u4ea7\u8005-\u6d88\u8d39\u8005\u6a21\u5f0f\uff1f\u5982\u4f55\u5b9e\u73b0\uff1f","previous_post_id":4043,"previous_post_title":"\u5173\u4e8eTCP\/IP\u7684\u9762\u8bd5\u9898\uff0c\u770b\u5b8c\u8fd9\u4e00\u7bc7\u5c31\u591f\u4e86","_links":{"self":[{"href":"https:\/\/xinchewhd.com.cn\/index.php\/wp-json\/wp\/v2\/posts\/4039","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/xinchewhd.com.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/xinchewhd.com.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/xinchewhd.com.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/xinchewhd.com.cn\/index.php\/wp-json\/wp\/v2\/comments?post=4039"}],"version-history":[{"count":0,"href":"https:\/\/xinchewhd.com.cn\/index.php\/wp-json\/wp\/v2\/posts\/4039\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/xinchewhd.com.cn\/index.php\/wp-json\/wp\/v2\/media\/4036"}],"wp:attachment":[{"href":"https:\/\/xinchewhd.com.cn\/index.php\/wp-json\/wp\/v2\/media?parent=4039"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/xinchewhd.com.cn\/index.php\/wp-json\/wp\/v2\/categories?post=4039"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/xinchewhd.com.cn\/index.php\/wp-json\/wp\/v2\/tags?post=4039"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}