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這樣，就只會監控localhost機器上test_user用戶發送過來的SQL。其他主機、其他用戶發過來的SQL統統不監控，執行如下SQL語句，開啓相關監控項:","attrs":{}}]},{"type":"blockquote","content":[{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/5b/5bb27d631f6d8c49ea8641bf29356637.png","alt":null,"title":null,"style":null,"href":null,"fromPaste":false,"pastePass":false}}],"attrs":{}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"使用開啓監控的用戶，執行SQL語句，比如:","attrs":{}}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/03/03d6a54cdc83fc25edf9c4604b092316.png","alt":null,"title":null,"style":null,"href":null,"fromPaste":false,"pastePass":false}}],"attrs":{}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"執行如下SQL，獲得語句的EVENT_ID。","attrs":{}}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/4f/4f3d4d1f90c17febef444b86658b3ee3.png","alt":null,"title":null,"style":null,"href":null,"fromPaste":false,"pastePass":false}}],"attrs":{}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":" 這一步類似於 show profiles。 執行如下SQL語句做性能分析，這樣就可以知道這條語句各種階段的信息了。","attrs":{}}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/c6/c6578c32f337c590300573a207983331.png","alt":null,"title":null,"style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":null,"fromPaste":true,"pastePass":true}},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"三種方式對比與選擇","attrs":{}}]},{"type":"bulletedlist","content":[{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":1,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"SHOW PROFILE：簡單、方便，已廢棄","attrs":{}}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":1,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"INFORMATION_SCHEMA：PROFILING，它和SHOW 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獨一無二的「MySQL調優金字塔」相信也許你擁有了它，你就很可能擁有了全世界。
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本篇文章會按照自上而下以及自下而上的兩種方向去“遊覽”【MySQL技術金字塔】，兩個方向分別是從成本出發的（潛臺詞就是便宜越好，照顧公司成本哦！），本章內容，可能有點多，希望大家慢慢消化，實在不行來片“嗎丁啉”，哈哈，開玩笑了！","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":" 主要技術分佈爲6大部分，如下圖金子圖所示：","attrs":{}}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/77/77ad3e9147e9bdbaaf04dfd3fc08cd4d.png","alt":null,"title":"","style":[{"key":"width","value":"50%"},{"key":"bordertype","value":"border"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"研發成本角度","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":" 從軟件的【研發成本】的角度而言：伴隨着優化的方向，從金字塔頂部像金字塔底部的方向進行過度，伴隨着高度越來越低，成本會越來越低，這個方向其實是非常考驗技術人員與項目管理者的能力的，但是它確實，老闆對象看到的，哈哈。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/b9/b9ffb92155df8a35cddcda93b5e6bb50.png","alt":null,"title":null,"style":null,"href":null,"fromPaste":false,"pastePass":false}}],"attrs":{}},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"實現效果角度","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":" 從軟件的【技術可行性和效果】的角度而言：伴隨着優化的方向，從金字塔低部像金字塔頂部的方向進行過度，伴隨着高度越來越高，成本會越來越高，耗費的財力和人力也會相對的有所降低，但是如果多花錢，老闆肯定不願意，比如，請一些行業大牛或者一些牛掰的服務器等，可以看出來正好與上面的方向相反。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/f3/f3e1c4f6682a273fc5d814e77f0e1545.png","alt":null,"title":null,"style":null,"href":null,"fromPaste":false,"pastePass":false}}],"attrs":{}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":" 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由三個步驟組成：發現問題、分析問題和解決問題。","attrs":{}}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"發現慢SQL及日誌","attrs":{}}]},{"type":"paragraph","attrs":{"indent":1,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"查詢慢SQL的日誌是MySQL內置的一個功能，可以記錄執行時間超過我們配置閾值的SQL語句。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"參數與默認值：","attrs":{}}]},{"type":"blockquote","content":[{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/81/814ad54bbb3a8788be441f01c05a206e.png","alt":null,"title":null,"style":null,"href":null,"fromPaste":false,"pastePass":false}}],"attrs":{}},{"type":"heading","attrs":{"align":null,"level":5},"content":[{"type":"text","text":"修改數據庫服務配置","attrs":{}}]},{"type":"numberedlist","attrs":{"start":1,"normalizeStart":1},"content":[{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":1,"align":null,"origin":null},"content":[{"type":"text","text":"修改我們安裝後的配置文件my.cnf，在[mysqld]段落中加入以上參數配置：","attrs":{}}]}]}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/b9/b9dfce31188a9b860b3f259f52e27fd0.png","alt":null,"title":"","style":[{"key":"width","value":"100%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"numberedlist","attrs":{"start":2,"normalizeStart":2},"content":[{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":2,"align":null,"origin":null},"content":[{"type":"text","text":"之後進行重啓服務","attrs":{}}]}]}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/0b/0bcfd4a0a87357718df904adfca4dbb4.png","alt":null,"title":"","style":[{"key":"width","value":"100%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"heading","attrs":{"align":null,"level":5},"content":[{"type":"text","text":"修改全局會話配置","attrs":{}}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/d9/d9fd3800acd47afbe28d8345d1ad70d5.png","alt":null,"title":"","style":[{"key":"width","value":"100%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":1,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":" 這種方式，不需要重啓就可以生效，但是當服務器重啓的時候，又會重新丟失配置。以上的配置可以","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"將慢查詢SQL記錄到mysql數據庫中的slow_log表中以及對應的slow_sql的文件中去。","attrs":{}}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"分析慢SQL及日誌","attrs":{}}]},{"type":"heading","attrs":{"align":null,"level":5},"content":[{"type":"text","text":"分析慢SQ的查詢日誌","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":" 查詢slow_log表，當根據上面的設置，當log_output設置爲TABLE的時候，就會將mysql的慢查詢日誌記錄到mysql.slow_log表中去，我們可以採用","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"select * from 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