0、导读
InnoDB Monitor总是被自动打开，为何
1、问题
问题来自于我们课堂上的一位同学，她反应InnoDB Monitor总是被莫名其妙打开，启用了审计以及general log功能都找不到这个“鬼”，很是郁闷。
2、原因
其实，认真翻看MySQL手册的话，应该就能注意到下面这段话（在 15.21 InnoDB Troubleshooting 这部分）：
InnoDB temporarily enables standard InnoDB Monitor output under the following conditions:
- A long semaphore wait
InnoDBcannot find free blocks in the buffer pool- Over 67% of the buffer pool is occupied by lock heaps or the adaptive hash index
如果您也遇到相似的情况，赶紧去优化MySQL吧，下面这些资料可能用得上，自取不谢 ：）
15.21 InnoDB Troubleshooting， http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting.html
</div><div class="article-inner" id="lark-content"><div class="lake-content-editor-core lake-engine lake-typography-traditional"><h1 style="text-align:justify;padding:7px 0px;margin:0px;font-weight:700;font-size:28px;line-height:36px">0、导读</h1><blockquote style="text-align:justify;margin-top:5px;margin-bottom:5px;padding-left:1em;margin-left:0px;border-left-width:3px;border-left-style:solid;border-left-color:rgb( 238 , 238 , 238 )"><p style="font-size:14px;color:rgb( 38 , 38 , 38 );line-height:1.74;letter-spacing:0.05em;outline-style:none;margin:0px">InnoDB Monitor总是被自动打开，为何</p></blockquote><h1 style="text-align:justify;padding:7px 0px;margin:0px;font-weight:700;font-size:28px;line-height:36px">1、问题</h1><p style="text-align:justify;font-size:14px;color:rgb( 38 , 38 , 38 );line-height:1.74;letter-spacing:0.05em;outline-style:none;margin:0px">问题来自于我们课堂上的一位同学，她反应InnoDB Monitor总是被莫名其妙打开，启用了审计以及general log功能都找不到这个“鬼”，很是郁闷。</p><h1 style="text-align:justify;padding:7px 0px;margin:0px;font-weight:700;font-size:28px;line-height:36px">2、原因</h1><p style="text-align:justify;font-size:14px;color:rgb( 38 , 38 , 38 );line-height:1.74;letter-spacing:0.05em;outline-style:none;margin:0px">其实，认真翻看MySQL手册的话，应该就能注意到下面这段话（在 15.21 InnoDB Troubleshooting 这部分）：</p><p style="text-align:justify;font-size:14px;color:rgb( 38 , 38 , 38 );line-height:1.74;letter-spacing:0.05em;outline-style:none;margin:0px"><code style="font-family:monospace;font-size:inherit;background-color:rgba( 0 , 0 , 0 , 0.0588235 );padding:0px 2px;border:1px solid rgba( 0 , 0 , 0 , 0.0784314 );border-top-left-radius:2px;border-top-right-radius:2px;border-bottom-right-radius:2px;border-bottom-left-radius:2px;line-height:inherit;text-indent:0px">InnoDB</code> temporarily enables standard <code style="font-family:monospace;font-size:inherit;background-color:rgba( 0 , 0 , 0 , 0.0588235 );padding:0px 2px;border:1px solid rgba( 0 , 0 , 0 , 0.0784314 );border-top-left-radius:2px;border-top-right-radius:2px;border-bottom-right-radius:2px;border-bottom-left-radius:2px;line-height:inherit;text-indent:0px">InnoDB</code> Monitor output under the following conditions:</p><ul style="text-align:justify;list-style-type:disc;margin:0px;padding-left:23px;font-size:14px;color:rgb( 38 , 38 , 38 );line-height:1.74;letter-spacing:0.05em;outline-style:none"><li>A long semaphore wait<br /></li><li><code style="font-family:monospace;font-size:inherit;background-color:rgba( 0 , 0 , 0 , 0.0588235 );padding:0px 2px;border:1px solid rgba( 0 , 0 , 0 , 0.0784314 );border-top-left-radius:2px;border-top-right-radius:2px;border-bottom-right-radius:2px;border-bottom-left-radius:2px;line-height:inherit;text-indent:0px">InnoDB</code> cannot find free blocks in the buffer pool<br /></li><li>Over 67% of the buffer pool is occupied by lock heaps or the adaptive hash index<br /></li></ul><p style="text-align:justify;font-size:14px;color:rgb( 38 , 38 , 38 );line-height:1.74;letter-spacing:0.05em;outline-style:none;margin:0px">如果您也遇到相似的情况，赶紧去优化MySQL吧，下面这些资料可能用得上，自取不谢 ：）</p><p style="text-align:justify;font-size:14px;color:rgb( 38 , 38 , 38 );line-height:1.74;letter-spacing:0.05em;outline-style:none;margin:0px"><span style="color:rgb( 62 , 62 , 62 );font-size:19px" class="lake-fontsize-14">15.21 InnoDB Troubleshooting， </span><u><a href="http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting.html" target="_blank" rel="noopener noreferrer">http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting.html</a></u></p><p style="text-align:justify;font-size:14px;color:rgb( 38 , 38 , 38 );line-height:1.74;letter-spacing:0.05em;outline-style:none;margin:0px"><a href="http://mp.weixin.qq.com/s?__biz=MjM5NzAzMTY4NQ==&mid=205830212&idx=1&sn=c018f0903454b34196081bb79c244be5&scene=21#wechat_redirect" target="_blank" rel="noopener noreferrer">比较全面的MySQL优化参考（上篇）</a></p><p style="text-align:justify;font-size:14px;color:rgb( 38 , 38 , 38 );line-height:1.74;letter-spacing:0.05em;outline-style:none;margin:0px"><a href="http://mp.weixin.qq.com/s?__biz=MjM5NzAzMTY4NQ==&mid=205830212&idx=2&sn=ee2162050162a32bd29802b001386abe&scene=21#wechat_redirect" target="_blank" rel="noopener noreferrer">比较全面的MySQL优化参考（下篇）</a></p><p style="text-align:justify;font-size:14px;color:rgb( 38 , 38 , 38 );line-height:1.74;letter-spacing:0.05em;outline-style:none;margin:0px"><a href="http://mp.weixin.qq.com/s?__biz=MjM5NzAzMTY4NQ==&mid=200809436&idx=1&sn=91304b670535a702cf52ff3c0d5d40b4&scene=21#wechat_redirect" target="_blank" rel="noopener noreferrer">20141024程序员节分享： 步到位实现MySQL优化</a></p></div></div>
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