Solved

resizing rollback segments

Posted on 2011-03-21
4
564 Views
Last Modified: 2013-12-19
I have SUN Solaris 10 - Oracle 10.2.4
I tried using auto undo but performance was horrible - my Friday night archive never finished.
It ran for over 24 hours instead of 3 or 4 hours.

So I have put undo back to manual.
I want to resize the rollback segments to make them bigger.

1. Can I do this on the fly with production up and running.
2. How do I ensure that there is nothing being lost if I take a segment offline, drop it and recreate it?
3. initial and next are currently set 20 8k with optimal at 16k  - would 10 or 15k initial/next be better?
0
Comment
Question by:bkreynolds48
  • 2
4 Comments
 
LVL 73

Expert Comment

by:sdstuber
ID: 35182709
force several log switches, wait until "archived" becomes yes, then drop and recreate before the looping cycles back around to the one you're working with
0
 
LVL 34

Accepted Solution

by:
johnsone earned 500 total points
ID: 35182874
We are talking about rollback/undo segments, not redo.  Rollback/undo never gets to an archived status.

Yes, you can do this on the fly with production up and running.

Do not worry about losing information in offline segments.  Oracle will not let you drop the segment if there is a transaction that is using it.

I would still suggest that you do this when no large jobs are running.  There is a possibility you could create an artificial ORA-01555 because of dropping a segment.

Be sure when you are done dropping and creating the segments that you update the rollback_segs parameter.
0
 
LVL 73

Expert Comment

by:sdstuber
ID: 35183147
oops, right,

  read undo but put redo in my head

nevermind my post.

0
 
LVL 1

Author Closing Comment

by:bkreynolds48
ID: 35197759
Thanks and sorry for the delay my car engine blew yesterday while I was out of town.
0

Featured Post

PRTG Network Monitor: Intuitive Network Monitoring

Network Monitoring is essential to ensure that computer systems and network devices are running. Use PRTG to monitor LANs, servers, websites, applications and devices, bandwidth, virtual environments, remote systems, IoT, and many more. PRTG is easy to set up & use.

Join & Write a Comment

Why doesn't the Oracle optimizer use my index? Querying too much data Most Oracle developers know that an index is useful when you can use it to restrict your result set to a small number of the total rows in a table. So, the obvious side…
Subquery in Oracle: Sub queries are one of advance queries in oracle. Types of advance queries: •      Sub Queries •      Hierarchical Queries •      Set Operators Sub queries are know as the query called from another query or another subquery. It can …
This videos aims to give the viewer a basic demonstration of how a user can query current session information by using the SYS_CONTEXT function
This video shows how to configure and send email from and Oracle database using both UTL_SMTP and UTL_MAIL, as well as comparing UTL_SMTP to a manual SMTP conversation with a mail server.

747 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

11 Experts available now in Live!

Get 1:1 Help Now