{"id":5645,"date":"2021-04-27T09:43:36","date_gmt":"2021-04-27T01:43:36","guid":{"rendered":"https:\/\/www.gbase8.cn\/?p=5645"},"modified":"2021-05-07T13:30:10","modified_gmt":"2021-05-07T05:30:10","slug":"%e6%95%b0%e6%8d%ae%e5%ba%93%e9%81%bf%e5%85%8d%e6%95%b0%e6%8d%ae%e9%83%a8%e5%88%86%e5%86%99%e5%85%a5%e7%9a%84full_page_writes%e5%92%8cdouble-write%e6%9c%ba%e5%88%b6%e4%b8%aa%e4%ba%ba%e7%90%86%e8%a7%a3","status":"publish","type":"post","link":"https:\/\/www.gbase8.cn\/en\/5645","title":{"rendered":"\u6570\u636e\u5e93\u907f\u514d\u6570\u636e\u90e8\u5206\u5199\u5165\u7684FULL_PAGE_WRITES\u548cdouble write\u673a\u5236\u4e2a\u4eba\u7406\u89e3"},"content":{"rendered":"<p>\u6570\u636e\u5e93\u907f\u514d\u6570\u636e\u90e8\u5206\u5199\u5165\u7684FULL_PAGE_WRITES\u548cdouble write\u673a\u5236\u4e2a\u4eba\u7406\u89e3<\/p>\n\n\n\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_84 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Directory Navigation<\/p>\n<label for=\"ez-toc-cssicon-toggle-item-6a2d50654e19f\" class=\"ez-toc-cssicon-toggle-label\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewbox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewbox=\"0 0 24 24\" version=\"1.2\" baseprofile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/label><input type=\"checkbox\"  id=\"ez-toc-cssicon-toggle-item-6a2d50654e19f\"  aria-label=\"Toggle\" \/><nav><ul class='ez-toc-list ez-toc-list-level-1' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.gbase8.cn\/en\/5645\/#%E5%8F%82%E8%80%83\" >\u53c2\u8003<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.gbase8.cn\/en\/5645\/#FULL_PAGE_WRITES\" >FULL_PAGE_WRITES<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.gbase8.cn\/en\/5645\/#%E6%A0%B8%E5%BF%83\" >\u6838\u5fc3<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.gbase8.cn\/en\/5645\/#%E7%90%86%E8%A7%A3\" >\u7406\u89e3<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.gbase8.cn\/en\/5645\/#double_write\" >double write<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.gbase8.cn\/en\/5645\/#%E6%A0%B8%E5%BF%83-2\" >\u6838\u5fc3<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.gbase8.cn\/en\/5645\/#%E7%90%86%E8%A7%A3-2\" >\u7406\u89e3<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.gbase8.cn\/en\/5645\/#%E6%80%BB%E7%BB%93\" >Summary<\/a><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E5%8F%82%E8%80%83\"><\/span>\u53c2\u8003<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p><a href=\"http:\/\/blog.chinaunix.net\/uid-20726500-id-5105905.html\">http:\/\/blog.chinaunix.net\/uid-20726500-id-5105905.html<br><\/a><a href=\"https:\/\/www.cnblogs.com\/geaozhang\/p\/7241744.html\">https:\/\/www.cnblogs.com\/geaozhang\/p\/7241744.html<\/a><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"FULL_PAGE_WRITES\"><\/span>FULL_PAGE_WRITES<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E6%A0%B8%E5%BF%83\"><\/span>\u6838\u5fc3<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>PostgreSQL\u5f15\u5165\u4e86full<em>page<\/em>writes\uff0ccheckpoint\u540e\u7684\u7b2c\u4e00\u6b21\u9875\u9762\u4fee\u6539\u5c06\u5b8c\u5168\u7684\u9875\u5185\u5bb9\u8bb0\u5f55\u5230WAL\uff0c\u4e4b\u540e\u4ece\u4e0a\u6b21\u7684checkpoint\u70b9\u5f00\u59cb\u6062\u590d\u65f6\uff0c\u5148\u53d6\u5f97\u8fd9\u4e2a\u5b8c\u6210\u7684\u9875\u9762\u5185\u5bb9\u7136\u540e\u518d\u5728\u5176\u4e0a\u91cd\u653e\u540e\u7eed\u7684\u4fee\u6539\u64cd\u4f5c\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E7%90%86%E8%A7%A3\"><\/span>\u7406\u89e3<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>\u5199\u5165\u524d\uff0c\u5c06\u6574\u4e2a\u539f\u59cb\u9875\u9762\u5168\u90e8\u7559\u4e00\u4e2a\u526f\u672c\uff0c\u7136\u540e\u505a\u5bf9\u5e94\u7684\u4fee\u6539\u5e76\u8bb0\u5f55REDO\u65e5\u5fd7\u3002 \u6062\u590d\u65f6\uff0cWAL\u91cc\u6709\u5b8c\u6574\u7684\u539f\u59cb\u5185\u5bb9\uff0c\u6839\u636echeckpoint\u91cd\u505a\u5c31\u884c\u4e86\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"double_write\"><\/span>double write<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"694\" height=\"491\" src=\"https:\/\/www.gbase8.cn\/wp-content\/uploads\/2021\/04\/image-23.png\" alt=\"\" class=\"wp-image-5650\"\/><figcaption>double write \u793a\u610f\u56fe<\/figcaption><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E6%A0%B8%E5%BF%83-2\"><\/span>\u6838\u5fc3<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>1\u3001\u5f53\u4e00\u7cfb\u5217\u673a\u5236\u89e6\u53d1\u6570\u636e\u7f13\u51b2\u6c60\u4e2d\u7684\u810f\u9875\u5237\u65b0\u65f6\uff0c\u5e76\u4e0d\u76f4\u63a5\u5199\u5165\u78c1\u76d8\u6570\u636e\u6587\u4ef6\u4e2d\uff0c\u800c\u662f\u5148\u62f7\u8d1d\u81f3\u5185\u5b58\u4e2d\u7684doublewrite buffer\u4e2d\uff1b<\/p>\n\n\n\n<p>\u3000\u30002\u3001\u63a5\u7740\u4ece\u4e24\u6b21\u5199\u7f13\u51b2\u533a\u5206\u4e24\u6b21\u5199\u5165\u78c1\u76d8\u5171\u4eab\u8868\u7a7a\u95f4\u4e2d(\u8fde\u7eed\u5b58\u50a8\uff0c\u987a\u5e8f\u5199\uff0c\u6027\u80fd\u5f88\u9ad8)\uff0c\u6bcf\u6b21\u51991MB\uff1b<\/p>\n\n\n\n<p>\u3000\u30003\u3001\u5f85\u7b2c\u4e8c\u6b65\u5b8c\u6210\u540e\uff0c\u518d\u5c06doublewrite buffer\u4e2d\u7684\u810f\u9875\u6570\u636e\u5199\u5165\u5b9e\u9645\u7684\u5404\u4e2a\u8868\u7a7a\u95f4\u6587\u4ef6(\u79bb\u6563\u5199)\uff1b(\u810f\u9875\u6570\u636e\u56fa\u5316\u540e\uff0c\u5373\u8fdb\u884c\u6807\u8bb0\u5bf9\u5e94doublewrite\u6570\u636e\u53ef\u8986\u76d6)<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E7%90%86%E8%A7%A3-2\"><\/span>\u7406\u89e3<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>\u6570\u636e\u5148\u987a\u5e8f\u5199\u5165\u5230\u4e00\u4e2a\u4e34\u65f6\u6587\u4ef6\uff0c\u786e\u8ba4\u6210\u529f\u540e\uff0c\u518d\u5c06\u4e34\u65f6\u6587\u4ef6\u3010\u968f\u673a\u3011\u8f6c\u5b58\u5230\u6b63\u5f0f\u6570\u636e\u7a7a\u95f4\u3002<\/p>\n\n\n\n<p><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E6%80%BB%E7%BB%93\"><\/span>Summary<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>FULL_PAGE_WRITES \u6bcf\u6b21\u90fd\u8981\u4fdd\u5b58\u4e00\u4efd\u539f\u59cb\u7684\u5b8c\u6574\u6570\u636e\uff0c\u589e\u52a0\u4e86\u603b\u91cf\u3002<\/p>\n\n\n\n<p>double write\uff0c\u53ea\u8bb0\u5f55\u53d8\u52a8\uff0c\u4f46\u9700\u8981\u4e8c\u6b21\u5199\u5165(Double), \u591a\u4e86\u4e00\u6b21\u78c1\u76d8IO\u3002<\/p>\n\n\n\n<p>\u4ece\u6574\u4f53\u770b\uff0cdouble write\u66f4\u9002\u5408\u5927\u6570\u636e\u91cf\u5199\u5165<\/p>","protected":false},"excerpt":{"rendered":"<p>\u6570\u636e\u5e93\u907f\u514d\u6570\u636e\u90e8\u5206\u5199\u5165\u7684FULL_PAGE_WRITES\u548cdouble write\u673a\u5236\u4e2a\u4eba\u7406\u89e3<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[100],"class_list":["post-5645","post","type-post","status-publish","format-standard","hentry","category-1","tag-100"],"_links":{"self":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/5645","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/comments?post=5645"}],"version-history":[{"count":5,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/5645\/revisions"}],"predecessor-version":[{"id":5651,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/5645\/revisions\/5651"}],"wp:attachment":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/media?parent=5645"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/categories?post=5645"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/tags?post=5645"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}