OraFAQ Forum: Performance Tuning » DBWR writes entire dirty block ?

Home » RDBMS Server » Performance Tuning » DBWR writes entire dirty block ?

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

DBWR writes entire dirty block ? [message #400272]

Mon, 27 April 2009 07:13

tridentadm
Messages: 142
Registered: March 2006

Senior Member

The DBWn process writes cold, dirty buffers to disk so that user
processes are able to find cold, clean buffers that can be used to read new blocks into the cache.

^^
I got this regarding DBWR in the Database Concepts guide.

What I am slightly confused about is :
Does the entire block get written or only some part of it ?
I think entire block is written.

If wrong then please correct/guide me ?

Report message to a moderator

Re: DBWR writes entire dirty block ? [message #400302 is a reply to message #400272]

Mon, 27 April 2009 08:12

Michel Cadot
Messages: 68664
Registered: March 2007
Location: Nanterre, France, http://...

Senior Member
Account Moderator

First ALWAYS post a link to the documentation you quote.
Then DBWR process changes with version, so post it too.

Block is the logical unit of io for Oracle.

Regards
Michel

Report message to a moderator

Re: DBWR writes entire dirty block ? [message #400327 is a reply to message #400272]

Mon, 27 April 2009 11:30

tridentadm
Messages: 142
Registered: March 2006

Senior Member

http://download-east.oracle.com/docs/cd/B19306_01/server.102/b14220/process.htm

I got it from the 9i Concepts guide.

Report message to a moderator

Re: DBWR writes entire dirty block ? [message #400331 is a reply to message #400327]

Mon, 27 April 2009 11:58

Michel Cadot
Messages: 68664
Registered: March 2007
Location: Nanterre, France, http://...

Senior Member
Account Moderator

I meant a link to what you quote not a whole chapter of 30 pages.
You need to help us help you by provinding the most precise information. If you expect us to make the effort to find what you easily post you will be disapointed and mourn why you have no answer.

Anyway you have the answer but think it for your next question.

Regards
Michel

Report message to a moderator

Re: DBWR writes entire dirty block ? [message #400333 is a reply to message #400272]

Mon, 27 April 2009 12:12

BlackSwan
Messages: 26766
Registered: January 2009
Location: SoCal

Senior Member

>I think entire block is written.
Operating system block or Oracle block?

Report message to a moderator

Previous Topic:	Hints USE_HASH (merged)
Next Topic:	Job queue process takes more then 90 % cpu

Goto Forum:

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

]

Current Time: Wed Jun 26 11:42:09 CDT 2024