vmware(workstation5.5.3)+windows2003 server+oracle10g r2安装体会备记

wisdomone1

context switches,这就是user mode和os mode的switch,会影响到性能.

gcs(global cache service):1,负责维护全局角色(数据块)的块模式.2,实例间的block transfer,
gcs使用lmsn(global cache service processes) and lmd(global enqueue service daemon)后台进程.

RAC中可以达到配置10个lmsn.

lmon:监控全局资源使用.它起一个和单实例smon同样的作用.处理在恢复中和全局资源相关的工作.

wisdomone1

imr(instance membership recovery)
  它建立一个集群节点是否heartbeat(表明节点实例定时活动的消息),
  讲白一些,就是它在控制文件中记录节点是否活动.

wisdomone1

哪位可以讲讲gc_files_io_locks.我看文档讲此参数最好用于mostly read-only.
看过文档还是不太懂.
此它可以用于override ges and gcs.
不知在RAC中,何时应用这个参数.(适用于special file or other)

wisdomone1

gc_files_io_locks:specify 关系(锁和文件)

Lock Assignment Examples

For example, you can assign 300 locks to file 1 and 100 locks to file 2 by adding the
following line to your initialization parameter file:
GC_FILES_TO_LOCKS = "1=300:2=100"
The following entry specifies a total of 1500 locks: 500 each for files 1, 2, and 3:
GC_FILES_TO_LOCKS = "1-3=500EACH"
By contrast, the following entry specifies a total of only 500 locks spread across the
three files:
GC_FILES_TO_LOCKS = "1-3=500"
The following entry indicates that Oracle should use 1000 distinct locks to protect
file 1. The data in the files is protected in groups of 25 contiguous locks.
GC_FILES_TO_LOCKS = "1=1000!25"

wisdomone1

GC_FILES_TO_LOCKS="{file_list=#locks[!blocks] [EACH][:]} . . ."

wisdomone1

add datafile(sets),就要重配置gc_files_to_locks.increase overhead.

wisdomone1

Never include the following types of files in the GC_FILES_TO_LOCKS parameter
list:
  Files that contain rollback segments.

Files that are part of a TEMPORARY tablespace.

Files with read-only data within a tablespace that is explicitly set to READ
ONLY; the exception to this is a single lock that you can assign to ensure the
tablespace does not have to contend for spare locks—but setting this lock is not
mandatory—you can still leave this tablespace unassigned

wisdomone1

If you set GC_FILES_TO_LOCKS, then Cache Fusion is disabled

wisdomone1

看看oracle document,看来rac tuning不是哪么容易啊.还要加深学习力度

wisdomone1

没有使用：lmt和aum,可以采用free lists or free list groups.
条件：要高insert 的对象．
select substr(sql_text,80),decode(command_type,2,'insert'),executions
from v$sql where command_types=2 order by executions;