RE: DBWR pegged out
- From: John Hallas <John.Hallas@xxxxxxxxxxxxxxxxxx>
- To: "dag@xxxxxxxxxxxxxxx" <dag@xxxxxxxxxxxxxxx>, "oracle-l@xxxxxxxxxxxxx" <oracle-l@xxxxxxxxxxxxx>
- Date: Tue, 8 Mar 2011 16:14:57 +0000
From the Ixora site
If the bandwidth is inadequate at any point, you will see free buffer waits. If
the bandwidth is lower at the operating system or hardware level than at the
Oracle level, then you will see substantial write complete waits.
Free buffer waits and write complete waits are opposite types of DBWn problem.
Generally, the first indicates that the write bandwidth is too small, and the
second indicates that Oracle internal write batch size (_db_block_write_batch)
is too big.
In my view this is a problem with writing down to disk and is an OS I/O issue
www.jhdba.wordpress.com
-----Original Message-----
From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On
Behalf Of Doug Gernaat
Sent: 08 March 2011 15:55
To: oracle-l@xxxxxxxxxxxxx
Subject: DBWR pegged out
after oracle suggested bumping up db_writer_processes from 2 to 4, at times it
is still getting pegged out. "write complete waits" will become a top time
event.
drilling down will show:
______________________________________________________________________
Wm Morrison Supermarkets Plc is registered in England with number 358949. The
registered office of the company is situated at Gain Lane, Bradford, West
Yorkshire BD3 7DL. This email and any attachments are intended for the
addressee(s) only and may be confidential.
If you are not the intended recipient, please inform the sender by replying to
the email that you have received in error and then destroy the email.
If you are not the intended recipient, you must not use, disclose, copy or rely
on the email or its attachments in any way.
This email does not constitute a contract in writing for the purposes of the
Law of Property (Miscellaneous Provisions) Act 1989.
Our Standard Terms and Conditions of Purchase, as may be amended from time to
time, apply to any contract that we enter into. The current version of our
Standard Terms and Conditions of Purchase is available at:
http://www.morrisons.co.uk/gscop
Although we have taken steps to ensure the email and its attachments are
virus-free, we cannot guarantee this or accept any responsibility,
and it is the responsibility of recipients to carry out their own virus checks.
______________________________________________________________________
--
//www.freelists.org/webpage/oracle-l
Other related posts:
