{"id":340622,"date":"2021-02-12T02:19:53","date_gmt":"2021-02-11T18:19:53","guid":{"rendered":"http:\/\/4563.org\/?p=340622"},"modified":"2021-02-12T02:19:53","modified_gmt":"2021-02-11T18:19:53","slug":"postgresql-%e4%b8%ba%e4%bb%80%e4%b9%88%e4%b8%8d%e4%bd%bf%e7%94%a8-direct-io%ef%bc%8c%e8%80%8c%e8%a6%81%e4%be%9d%e8%b5%96-os-page-cahce%ef%bc%9f","status":"publish","type":"post","link":"http:\/\/4563.org\/?p=340622","title":{"rendered":"PostgreSQL \u4e3a\u4ec0\u4e48\u4e0d\u4f7f\u7528 direct IO\uff0c\u800c\u8981\u4f9d\u8d56 os page cahce\uff1f"},"content":{"rendered":"
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PostgreSQL \u4e3a\u4ec0\u4e48\u4e0d\u4f7f\u7528 direct IO\uff0c\u800c\u8981\u4f9d\u8d56 os page cahce\uff1f <\/h1>\n

<\/p>\n

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\u8cc7\u6df1\u5927\u4f6c : zzkde <\/span> <\/i> 3<\/span> <\/div>\n
<\/div>\n<\/p><\/div>\n<\/p><\/div>\n<\/p><\/div>\n
<\/p>\n

\u5927\u591a\u6570\u4e3b\u6d41\u6570\u636e\u5e93\u90fd\u4f1a\u4f7f\u7528 direct IO\uff0c\u4f46 PostgreSQL \u4e3a\u5565\u4e0d\u4f7f\u7528\uff1f\u662f\u51fa\u4e8e\u4ec0\u4e48\u8003\u8651\u5462\uff1f\u6211\u7684\u7406\u89e3\u662f\u4e0d\u4f7f\u7528 direct IO\uff0c\u5728 buffer pool \u548c os page cahce \u90fd\u5b58\u4e00\u4efd\uff0c\u53cc\u91cd\u5f00\u9500\uff0c\u5185\u5b58\u5229\u7528\u7387\u5dee\u3002\u6027\u80fd\u4f9d\u8d56\u5404\u4e2a\u64cd\u4f5c\u7cfb\u7edf\u5b9e\u73b0\u7684 os page cahce\uff0c\u4e0d\u80fd\u4fdd\u8bc1\u8de8 OS \u95f4\u7684\u4e00\u81f4\u6027\u3002\u800c\u4e14\u4e0d\u597d\u505a\u9694\u79bb\u5565\u7684\uff0c\u6bd4\u5982\u591a\u4e2a postgreSQL \u5b9e\u4f8b\u5728\u540c\u4e00\u53f0\u8ba1\u7b97\u673a\u4e0a os page cache \u51b2\u7a81\u7684\u95ee\u9898\uff0c\u4e0d\u77e5\u9053 docker \u80fd\u5426\u5728\u8fd9\u4e2a\u5c42\u9762\u4e0a\u505a\u9694\u79bb\uff1f<\/p>\n<\/p><\/div>\n

\u5927\u4f6c\u6709\u8a71\u8aaa<\/b> (6<\/span>) <\/div>\n
<\/div>\n<\/p><\/div>\n<\/p><\/div>\n
    \n
  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : Aoang <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u8bbe\u8ba1\u95ee\u9898\uff0c\u771f\u60f3\u77e5\u9053\u6700\u521d\u7684\u539f\u56e0\u2026\u53ef\u80fd\u53ea\u80fd\u95ee\u90a3\u7fa4\u4eba\u4e86\uff0c\u4e0d\u8fc7\u8fd8\u662f\u53ef\u4ee5\u731c\u4e00\u731c\u7684\u3002<\/p>\n

    PostgreSQL \u8bde\u751f\u4e8e\u5b9e\u9a8c\u5ba4\u4e2d\uff0c\u76ee\u7684\u662f\u4e3a\u4e86\u7814\u7a76\u6570\u636e\u5e93\u5185\u6838\u539f\u7406\u3002\u4f7f\u7528 buffer io \u80fd\u591f\u51cf\u5c11 IO \u6808\u7684\u5f00\u53d1\u91cf\uff0c\u4ece\u800c\u66f4\u52a0\u4e13\u6ce8\u4e8e\u6570\u636e\u5e93\u5185\u6838\u539f\u7406\uff0c\u6240\u4ee5 PostgreSQL \u624d\u4f1a\u6709\u76f8\u5f53\u4e30\u5bcc\u7684 SQL \u8bed\u6cd5\u3001\u6267\u884c\u7b97\u6cd5\u548c\u4f18\u79c0\u7684\u6267\u884c\u4f18\u5316\u5668\u7b49\u529f\u80fd\uff0c\u5f53\u7136\u8fd8\u53ef\u4ee5\u63d0\u4e00\u4e0b\u4f18\u79c0\u7684\u6269\u5c55\u6027\u3002<\/p>\n

    \u53e6\u5916\uff0cPostgreSQL \u91c7\u7528\u591a\u8fdb\u7a0b\u7684\u5e76\u53d1\u673a\u5236\uff0c\u591a\u8fdb\u7a0b\u548c\u591a\u7ebf\u7a0b\u5bf9\u5185\u5b58\u7684\u4f7f\u7528\u65b9\u5f0f\u4e0a\u5b58\u5728\u533a\u522b\u4e5f\u662f\u4e00\u4e2a\u539f\u56e0\uff0cpage cache \u53ef\u4ee5\u770b\u505a\u591a\u8fdb\u7a0b\u4e4b\u95f4\u7684\u4e00\u79cd\u6570\u636e\u5171\u4eab\u65b9\u5f0f\uff0c\u5728\u6d41\u590d\u5236\u4e2d\uff0c\u901a\u8fc7 buffer io \u4ece page cache \u8bfb\u53d6 wal \u53ef\u4ee5\u51cf\u5c11\u7269\u7406\u8bfb\u7684\u9891\u7387 <\/p><\/div>\n<\/p><\/div>\n<\/li>\n

  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : stabc <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u4ec0\u4e48\u662f”buffer pool “\uff1f”\u4e0d\u80fd\u4fdd\u8bc1\u8de8 OS \u95f4\u7684\u4e00\u81f4\u6027”\u662f\u4ec0\u4e48\u610f\u601d\uff1f <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : CRVV <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u968f\u4fbf\u641c\u4e86\u4e00\u4e0b<\/p>\n

    https:\/\/www.postgresql.org\/message-id\/4C1A6339.9080300%402ndquadrant.com<\/p>\n

    > every experiment I’ve ever seen that tries to add more direct I\/O to the database has failed to improve anything<\/p>\n

    \u8fd9\u4e2a\u5e16\u5b50\u6bd4\u8f83\u8001\u4e86\uff0c\u4f46 2020 \u5e74\u8fd8\u6709\u4eba\u5bf9\u6bd4\u6d4b\u8bd5\u4e86 Oracle \u548c PostgreSQL<\/p>\n

    https:\/\/fritshoogland.wordpress.com\/2020\/01\/25\/oracle-and-postgres-disk-io-performance\/<\/p>\n

    \u7ed3\u8bba\u662f PostgreSQL \u4e0d\u7528 Direct I\/O \u4f46\u67d0\u4e9b\u60c5\u51b5\u4e0b\u8fd8\u6bd4 Oracle \u5feb\u3002<\/p>\n

    \u5982\u679c\u518d\u641c\u4e00\u4e0b Linux Direct I\/O\uff0c\u4f1a\u627e\u5230\u5f88\u591a\u4eba\u8bf4\u8fd9\u73a9\u610f\u4e0d\u597d\u7528\uff0c\u5305\u62ec Linus Torvalds \u3002<\/p>\n

    \u8fd9\u4e48\u770b\u4e00\u5708\u4e0b\u6765\uff0c\u4e0d\u7528 Direct I\/O \u662f\u4e2a\u5f88\u6b63\u5e38\u7684\u51b3\u7b56\u4e86\uff1b\u5f53\u7136\u5982\u4e3b\u6240\u8bf4\uff0c\u7528 Direct I\/O \u4e5f\u6709\u4f18\u70b9\u7528\u5b83\u5f53\u7136\u4e5f\u662f\u5408\u9002\u7684\u3002 <\/p><\/div>\n<\/p><\/div>\n<\/li>\n

  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : wevsty <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u4f9d\u8d56 OS \u63d0\u4f9b\u7684 Cahce \u624d\u80fd\u4fdd\u8bc1\u8de8 OS \u7684\u4e00\u81f4\u6027\uff0c\u4e0d\u7136\u5404\u79cd\u5e73\u53f0 API \u53ef\u80fd\u90fd\u4e0d\u4e00\u6837\uff0c\u5c31\u5b8c\u5168\u5f97\u81ea\u5df1\u53bb\u5c01\u88c5\u51fa\u4e00\u5957 IO \u6846\u67b6\u3002
    \u81ea\u5df1\u5bf9\u5e95\u5c42 IO \u5c01\u88c5\u7684\u8bdd\uff0c\u8981\u8de8 OS \u591a\u5c11\u90fd\u662f\u8981\u505a\u51fa\u727a\u7272\u7684\uff0c\u800c\u4e14\u5f00\u53d1\u7ef4\u62a4\u4f1a\u66f4\u52a0\u9ebb\u70e6\u3002 <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : laminux29 <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u6ca1\u8bb0\u9519\u7684\u8bdd\uff0c\u8fd9\u6570\u636e\u5e93\u8fde\u5185\u5b58\u8868\u90fd\u6ca1\u652f\u6301\u5230\u4f4d\uff0c\u4f5c\u8005\u5728\u89e3\u91ca\u8fd9\u4e2a\u95ee\u9898\u65f6\u8fd8\u627e\u4e86\u501f\u53e3\u3002<\/p>\n

    \u76ee\u524d\u4f20\u7edf\u6570\u636e\u5e93\uff0c\u529f\u80fd\u6700\u9f50\u5168\u7684\uff0c\u5e94\u8be5\u5c31\u662f Oracle\uff0c\u53ef\u60dc\u8d35\u4e86\u70b9\u3002 <\/p><\/div>\n<\/p><\/div>\n<\/li>\n

  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : zhangysh1995 <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    @stabc \u597d\u95ee\u9898\u3002\u4e3b\u6ca1\u89e3\u91ca\u6e05\u695a\u611f\u89c9\u8ba8\u8bba\u6ca1\u4ec0\u4e48\u5fc5\u8981\u3002 <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n","protected":false},"excerpt":{"rendered":"

    PostgreSQL \u4e3a\u4ec0\u4e48\u4e0d\u4f7f\u7528…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[],"tags":[],"_links":{"self":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/340622"}],"collection":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=340622"}],"version-history":[{"count":0,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/340622\/revisions"}],"wp:attachment":[{"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=340622"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=340622"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=340622"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}