{"id":26,"date":"2015-06-02T10:33:16","date_gmt":"2015-06-02T02:33:16","guid":{"rendered":"http:\/\/www.q25.net\/?p=26"},"modified":"2015-06-02T10:33:16","modified_gmt":"2015-06-02T02:33:16","slug":"%e4%bd%bf%e7%94%a8timedd%e6%b5%8b%e8%af%95%e7%a1%ac%e7%9b%98%e8%af%bb%e5%86%99%e9%80%9f%e5%ba%a6","status":"publish","type":"post","link":"http:\/\/www.q25.net\/?p=26","title":{"rendered":"\u4f7f\u7528time+dd\u6d4b\u8bd5\u786c\u76d8\u8bfb\u5199\u901f\u5ea6"},"content":{"rendered":"<p>\u5199\u901f\u5ea6\uff1a<\/p>\n<p>time dd if=\/dev\/zero of=test.db bs=8k count=300000<br \/>\n\u5176\u4e2d\/dev\/zero\u662f\u4e00\u4e2a\u4f2a\u8bbe\u5907\uff0c\u5b83\u53ea\u4ea7\u751f\u7a7a\u5b57\u7b26\u6d41\uff0c\u5bf9\u5b83\u4e0d\u4f1a\u4ea7\u751fIO\uff0c\u6240\u4ee5\uff0cIO\u90fd\u4f1a\u96c6\u4e2d\u5728of\u6587\u4ef6\u4e2d\uff0cof\u6587\u4ef6\u53ea\u7528\u4e8e\u5199\uff0c\u6240\u4ee5\u8fd9\u4e2a\u547d\u4ee4\u76f8\u5f53\u4e8e\u6d4b\u8bd5\u78c1\u76d8\u7684\u5199\u80fd\u529b\u3002<\/p>\n<p>\u8f93\u51fa\u7684\u7ed3\u679c\u7c7b\u4f3c(\u56e0\u4e3a\u4e00\u822c\u66f4\u957f\u6d4b\u8bd5\u65f6\u95f4\u66f4\u51c6\u786e\uff0c\u6240\u4ee5\u53ef\u4ee5\u8bbe\u7f6ecount\u5927\u4e00\u4e9b)\uff1a<br \/>\n300000+0 records in<br \/>\n300000+0 records out<\/p>\n<p>real    0m36.669s<br \/>\nuser    0m0.185s<br \/>\nsys    0m9.340s<\/p>\n<p>\u5199\u901f\u5ea6\u4e3a\uff1a8*300000\/1024\/36.669=63.916M\/s<\/p>\n<p>\u8bfb\u901f\u5ea6\uff1a<\/p>\n<p>time dd if=\/dev\/sda1 of=\/dev\/null bs=8k<br \/>\n\u56e0\u4e3a\/dev\/sdb1\u662f\u4e00\u4e2a\u7269\u7406\u5206\u533a\uff0c\u5bf9\u5b83\u7684\u8bfb\u53d6\u4f1a\u4ea7\u751fIO\uff0c\/dev\/null\u662f\u4f2a\u8bbe\u5907\uff0c\u76f8\u5f53\u4e8e\u9ed1\u6d1e\uff0cof\u5230\u8be5\u8bbe\u5907\u4e0d\u4f1a\u4ea7\u751fIO\uff0c\u6240\u4ee5\uff0c\u8fd9\u4e2a\u547d\u4ee4\u7684IO\u53ea\u53d1\u751f\u5728\/dev\/sdb1\u4e0a\uff0c\u4e5f\u76f8\u5f53\u4e8e\u6d4b\u8bd5\u78c1\u76d8\u7684\u8bfb\u80fd\u529b<\/p>\n<p>\u8f93\u51fa\u7684\u7ed3\u679c\u7c7b\u4f3c\uff1a<br \/>\n448494+0 records in<br \/>\n448494+0 records out<\/p>\n<p>real    0m51.070s<br \/>\nuser    0m0.054s<br \/>\nsys    0m10.028s<\/p>\n<p>sda1\u4e0a\u7684\u8bfb\u53d6\u901f\u5ea6\u4e3a\uff1a8*448494\/1024\/51.070=68.61M\/s<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5199\u901f\u5ea6\uff1a time dd if=\/dev&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"_links":{"self":[{"href":"http:\/\/www.q25.net\/index.php?rest_route=\/wp\/v2\/posts\/26"}],"collection":[{"href":"http:\/\/www.q25.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.q25.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.q25.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.q25.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=26"}],"version-history":[{"count":1,"href":"http:\/\/www.q25.net\/index.php?rest_route=\/wp\/v2\/posts\/26\/revisions"}],"predecessor-version":[{"id":27,"href":"http:\/\/www.q25.net\/index.php?rest_route=\/wp\/v2\/posts\/26\/revisions\/27"}],"wp:attachment":[{"href":"http:\/\/www.q25.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=26"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.q25.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=26"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.q25.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=26"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}