分析解决11gR2 双节点RAC环境下的gc cr block busy_gc buffer busy acquire等待

系统环境OracleAWR里展示出来的各种症状(数据来自实例2)!1756815197506-a96c4dee-6df1-4b22-bc83-715579844d44.png

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了解gc buffer busy acquire和gc cr block busygc buffer busy acquire与gc cr block busy有何联系!1756815197899-d701bf4e-2168-4876-b1fd-24282fc5c928.png

定位修改源头,模拟gc cr block busy等待!1756815197956-c8fd0d27-d0f3-4663-ad10-197ee3e0b274.png

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找到生产环境里update后没有及时commit的证据!1756815198239-c53507c5-2075-4c1b-b53f-bb0e09be7d48.png

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深入gc cr block busy!1756815198408-52a633f2-cc3a-4cda-b245-952663b9be26.png

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本地节点select远程节点cache里未提交的数据块开销到底有多大17.99s17.72s!1756815198671-fcfe25b5-8863-45e4-ae6c-3c0c76a289aa.png

485.89s485.91s!1756815198745-61354556-7088-4330-affe-06f957f8ed95.png

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501.94s482.88s!1756815198869-1b78b89b-bbde-47b7-9891-725e659b3073.png

优化举措这个案例告诉我们Oraclehttp://www.linuxidc.com/topicnews.aspx?tid=12本文永久更新链接地址http://www.linuxidc.com/Linux/2016-06/132674.htm