about parallel

目前机器通常都是多core CPU,单个进程未开并行只会在一个core上运行,未完全发挥多core的特性,有时在统计查询,DML,DDL时需要开启并行提高效率

remove a node from 11g r2 rac on OEL5(删除节点)

[grid@znode1 bin]$ cluvfy stage -post nodedel -n racnode3 -verbose
Performing post-checks for node removal
Checking CRS integrity…
Clusterware version consistency passed
The Oracle Clusterware is healthy on node “znode2”
The Oracle Clusterware is healthy on node “znode1”
CRS integrity check passed
Result:
Node removal check passed
Post-check for node removal was successful.

修改11g r2 RAC SCAN IP

SCAN简化了客户端连接的配置,只需指定SCAN Name在客户端的tnsnames.ora,不需要知道每个节点的vip就可以实现负载均衡
每个节点上的pmon会经常的发送本节点的负载情况到scan listener…

11G R2 Oracle Local Registry(OLR)

从oracle 11R2版本起在网格计算领域引进了新特性,其中之一就是grid Oracle Local Registry(OLR),做为oracle clusterware的一部分,有些人喜欢叫Oracle Local Repository,因为这repositery记录了本地资源的信息和配置..