rdbms

基于MHA 的MySQL高可用方案

March 25, 2013 Architecture, MYSQL No comments

aaqwsh与select同学测试的MHA文档,另外基于这个HA方案公司应该会部署一些核心应用。另外提供之前的MHA测试

[……]

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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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MySQL key partition and MongoDB TEST

March 8, 2013 mongodb, MYSQL, NoSQL, performance No comments

对于业务的激活码需求做了一次关于mysql,mongodb的比对.mysql分为normal,key partition 数量分别是1亿和10亿数据,mysql采用直接访问PK键,partition key为PK,mysql table size 为90G,mongodb table size为15[……]

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mysql sync-binlog 导致 poor IO performance

January 29, 2013 MYSQL, performance No comments

mysql 数据库 poor IO performance.从DELL 815(6disk raid 5,oel5.5) 迁移至 HP DL380 (14disk raid 1+0,rhl5.8)

当时的IO 表现 

avg-cpu:  %user   %nice %system %[......]
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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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Scripts: Monitor Tablespace space growth

January 10, 2013 maintain, oracle No comments

这个脚本可以监控tablespace 空间增长趋势,并且邮件通知到相关domain– 根据TOAD SPACE MANAGEMENT 修改

创建schema,tablespace,table:

create tablespace toad '+ARCH/data/tbs_ts[......]
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Block split and entry reorder

December 12, 2012 Internals, oracle No comments

今天跟研发的同学讨论到了这个问题,index block split过程中涉及到的重新排序问题.

SQL> create table idx_split (a number, b varchar2(1446), c date);   
 
Table created
 

SQ[......]
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Scripts: dbms_backup_restore modify dbid and db_name

December 5, 2012 Internals, oracle 1 comment

Scripts:dbms_backup_restore_dbid

eg:

Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Par[......]
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Oracle Bind Graduation 测试

November 28, 2012 Internals, oracle No comments

最近team 讨论 Bind Graduation 比较激烈,详细可以见上一篇文章,基于Bind Graduation 做了以下测试：

主要目的：

测试基于OCI JDBC 等接口的 Bind Graduation行为.针对目前Bind Graduation的行为,以及11.2.0.[……]

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Can not purge obsolete cursor in 11.2.0.3

November 28, 2012 11g, maintain, oracle No comments

11.2.0.3中Oracle引入了_cursor_obsolete_threshold隐藏参数，默认为100，表示一个parent cursor最多可以有100个child cursor;如果SQL需要第101个child cursor,则将该parent cursor and its 100 c[……]

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