OraFAQ Forum: Server Administration » where to set redo buffers initialize parameter values

Home » RDBMS Server » Server Administration » where to set redo buffers initialize parameter values

Show: Today's Messages :: Polls :: Message Navigator
E-mail to friend

where to set redo buffers initialize parameter values [message #167051]

Tue, 11 April 2006 00:39

raddisonlee
Messages: 29
Registered: March 2005

Junior Member

SQL> select * from v$sga;

NAME VALUE
-------------------- ----------
Fixed Size 454316
Variable Size 109051904
Database Buffers 503316480
Redo Buffers 667648

i can views the sga allocated on v$sga ;
questions:
1. where to set redo buffers values ?? in oracle9i init.ora files , i can pool size ,cache size e.g. but can't read about redo and undo
2. does the undo data blocks(roll segment ) exsits in memory ? do oracle will allocated a memory areas for undo ??? if treat it as log buffer or data buffer as well ???

Report message to a moderator

Re: where to set redo buffers initialize parameter values [message #167798 is a reply to message #167051]

Mon, 17 April 2006 03:12

lazycat
Messages: 57
Registered: November 2005

Member

select * from v$parameter where name like '%log_buffer'

alter system set log_buffer=1M;

2 in orale memory ,no space for undo
the undo segment is in the rollback segment in the datafile

the sga only have the cache of the newest data

Report message to a moderator

Re: where to set redo buffers initialize parameter values [message #167820 is a reply to message #167798]

Mon, 17 April 2006 05:24

tarundua
Messages: 1080
Registered: June 2005
Location: India

Senior Member

lazycat wrote on Mon, 17 April 2006 13:42

alter system set log_buffer=1M;

Log_buffer is not a dynamic parameter so can not be modified at the instance level. To increase/decrease the size of log buffer one need to make changes in the pfile (init file).

                LOG_BUFFER
Parameter type Integer
 
Default value 512 KB or 128 KB * CPU_COUNT, whichever is greater
 
Parameter class Static
 
Range of values Operating system-dependent

Even it's static in 10g also.

[Updated on: Mon, 17 April 2006 05:25]

Report message to a moderator

Re: where to set redo buffers initialize parameter values [message #167829 is a reply to message #167820]

Mon, 17 April 2006 05:58

Mahesh Rajendran
Messages: 10708
Registered: March 2002
Location: oracleDocoVille

Senior Member
Account Moderator

Just to add what Tarun has already said,
In 10g things are a little different.
http://www.orafaq.com/forum/t/61795/42800/

Report message to a moderator

Previous Topic:	pga documentation
Next Topic:	spfile

Goto Forum:

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

]

Current Time: Tue Feb 18 18:52:51 CST 2025