Re: Effect of number of extents on Oracle I/O performance
- From: japplewhite@xxxxxxxxxxxxx
- To: joel.wittenmyer@xxxxxxxxxxxxxxxxx
- Date: Fri, 13 Mar 2009 18:40:12 -0500
Number of extents is irrelevant, especially with Locally Managed
Tablespaces. Even in 8i I used to manage a database with huge interMedia
Text indexed tables with out-of-line CLOBs. The tables and/or LOB
segments had over 30,000 extents and we had subsecond response time to
interMedia-type queries on the CLOBs. And that was on a Windows2k server.
With LMTs I haven't worried about extents or the "fragmentation"
boogey-man in a decade.
Jack C. Applewhite - Database Administrator
Austin I.S.D. - MIS Department
512.414.9715 (wk) / 512.935.5929 (pager)
Niall Litchfield <niall.litchfield@xxxxxxxxx>
Sent by: oracle-l-bounce@xxxxxxxxxxxxx
03/13/2009 06:08 PM
Please respond to
niall.litchfield@xxxxxxxxx
To
joel.wittenmyer@xxxxxxxxxxxxxxxxx
cc
oracle-l@xxxxxxxxxxxxx
Subject
Re: Effect of number of extents on Oracle I/O performance
I haven't seen what you describe since about 7.3.4, perhaps you could
demonstrate what you mean so that we can try it out ourselves (I have a
likely 11g candidate in mind).
On Fri, Mar 13, 2009 at 10:50 PM, Joel Wittenmyer <
joel.wittenmyer@xxxxxxxxxxxxxxxxx> wrote:
In Oracle 8 and 9 we saw that at 1000 extents performance began to drop
off. At 2K extents it leapt, laughing maniacally off a cliff. I know
that 10g is supposed to handle much more than that without a problem.
Tens or hundreds of thousands perhaps? Does anyone have experience with
just what the new threshold might be? Or is the architecture such now
that it is no longer a consideration?
Thanks in Advance.
Joel Wittenmyer
Sr. Database Architect
Sr. Data Architect
HealthTrans
--
//www.freelists.org/webpage/oracle-l
--
Niall Litchfield
Oracle DBA
http://www.orawin.info
Other related posts:
