Home » RDBMS Server » Server Administration » Does my online redo switch occurs frequently? (Linux 10g)
Does my online redo switch occurs frequently? [message #349749] Tue, 23 September 2008 00:16 Go to next message
Bangla
Messages: 49
Registered: August 2008
Member
From the archived log backups I have seen the following things,

List of Archived Logs in backup set 2442
  Thrd Seq     Low SCN    Low Time           Next SCN   Next Time
  ---- ------- ---------- ------------------ ---------- ---------
  1    49181   916167829  18 JAN 08 11:38:01 916185211  18 JAN 08 11:40:04
  1    49182   916185211  18 JAN 08 11:40:04 916203239  18 JAN 08 11:43:04
  1    49183   916203239  18 JAN 08 11:43:04 916224471  18 JAN 08 11:48:44


See the timing 916167829
Quote:
18 JAN 08 11:38:01 916185211 18 JAN 08 11:40:04


Does it means that our online redo log switching is occurring frequently and need to enlarge the redo log size?

P.S: Don't we do any manual switching of redo log.

What is the impact of redo sizing over performance?
Re: Does my online redo switch occurs frequently? [message #349754 is a reply to message #349749] Tue, 23 September 2008 00:52 Go to previous messageGo to next message
Michel Cadot
Messages: 64144
Registered: March 2007
Location: Nanterre, France, http://...
Senior Member
Account Moderator
Quote:
Does it means that our online redo log switching is occurring frequently and need to enlarge the redo log size?

If it is rare, you don't need to, if you have a switch every 2 to 5 minutes each time, yes you should enlarge you redo logs.

Quote:
Don't we do any manual switching of redo log.

Have a look at archived log size, if it is smaller then you have a manual switch log (assuming you didn't set archive_lag_target).

Quote:
What is the impact of redo sizing over performance?

In short, during log switches other processes have to wait.

Regards
Michel
Re: Does my online redo switch occurs frequently? [message #349762 is a reply to message #349749] Tue, 23 September 2008 01:04 Go to previous messageGo to next message
Bangla
Messages: 49
Registered: August 2008
Member
from my above example for sequence 49181 log switched occurs within (11:40:04-11:38:01=)2 minute 03 seconds. Is not it?
Re: Does my online redo switch occurs frequently? [message #349766 is a reply to message #349762] Tue, 23 September 2008 01:17 Go to previous message
Michel Cadot
Messages: 64144
Registered: March 2007
Location: Nanterre, France, http://...
Senior Member
Account Moderator
Yes, it is.

Regards
Michel
Previous Topic: PX Idle Wait - Wait Event
Next Topic: how much time taken by the job to execute
Goto Forum:
  


Current Time: Fri Dec 09 11:28:18 CST 2016

Total time taken to generate the page: 0.09252 seconds