oracle

Some exadata disk tips

July 29, 2013 Exadata, oracle No comments

针对exadata最近频繁报出的IO error,做如下总结

data node alert

ORA-27603: 单元存储 I/O 错误, I/O 在磁盘 o/192.168.10.5/DATA_DM01_CD_08_dm01cel03 上失败, 偏移量 17331625984 (数[......]

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[12c new feature] 针对 pluggable database的操作

July 5, 2013 12c, oracle No comments

1. create Pluggable database from NON_CDB database.

[oracle@db-42 ~]$ ora si 

SQL*Plus: Release 12.1.0.1.0 Production on Fri Jul 5 13:07:08 20[......]

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how to study oracle and some useful habits

July 4, 2013 advanced tech, oracle No comments

最近做的一次内部交流文档[……]

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[12c new feature] slow IO tracing by views

July 3, 2013 12c, oracle No comments

根据JL,Glen Fawcett 的文章 oracle 从12c开始提供了3个视图来探测慢速的IO

SQL> desc V$LGWRIO_OUTLIER;
 Name					   Null?    Type
 -----------------------------------[......]

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[12c new feature] add column enhancement

June 27, 2013 12c, oracle 1 comment

首先我们看一组测试 数据库版本oracle 12c beta1

SQL> select count(*) from test;

  COUNT(*)
----------
    725888

SQL> set timing on;
SQL> alter[......]

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ASM memory fragment problem in 11gR2 RAC

June 7, 2013 oracle, RAC No comments

前天处理了一启RAC ASM 内存泄露问题,系统为公司最后一套RAC one node 版本为11.2.0.3

这套核心RAC one node系统出现大量 log file switch buffer busy waits等待,并伴随大量cursor: pin S wait on X re[……]

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How to control CF calculation

May 14, 2013 Internals, oracle No comments

根据Richard Foote的文章,做了如下验证:

RefClustering Factor Calculation Improvement and provide some control over DBMS_STATS index clustering factor computat[……]

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Optimizer in Oracle 11g by wwf.

April 11, 2013 11g, advanced tech, oracle No comments

By wwf from ebay COC about Optimizer in Oracle 11g.

[……]

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Update exadata flash disk firmware due to poor performance on X2-2

March 14, 2013 Exadata, oracle No comments

ASR XD报警抛出如下错误

"
dm01cel02: Hardware Error has been detected in the Flash Logs on the Cell Node
dm01cel02: Please open up a Service Request[......]

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Active dataguard tips

January 23, 2013 oracle, replication No comments

11g ADG 给了大家更多的灾备选择,包括之前美国飓风,给了ADG大放光彩的机会,但是ADG并没有想象中的那么完美,以下是最近的一个CASE,具体过程不详写了,目前这个case还在跟进中,记录之:

[oracle@dcb-srv-0174 trace]$ cat itemstd02_ora_[......]

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