Re: Unusual Log Switching

Paul Brewer wrote:
>
> "Connor McDonald" <connor_mcdonald_at_yahoo.com> wrote in message
> news:3D499D69.26CC_at_yahoo.com...
> > Eric Kimble wrote:
> > >
> > > Rick, The system is non OPS so only single thread. I am the only DBA and
> have
> > > not been playing around with switching logfiles manually. It doesn't
> happen at
> > > the same time each month. One month it will be at 9am and the next it
> will be
> > > at 2am. I'm having difficulty finding a good pattern with it. I do
> assume the
> > > logs are actually full, the archived size is 2M for each file. I suppose
> I
> > > could go through with logminer and take a look and see what is going on?
> So to
> > > answer the first question is I think it is because of excessive redo
> > > generation but I don't know how to narrow down the culprit. (maybe I
> need a
> > > beer first?)
> > >
> > > Rick Anderson wrote:
> > >
> > > > Eric,
> > > >
> > > > Are the logs full? In other words, is the log switching occurring
> because
> > > > of excessive redo generation.
> > > >
> > > > Does the alert log indicate that perhaps a manual ALTER SYSTEM SWITCH
> > > > LOGFILE occurred?
> > > >
> > > > Is this an OPS environment (i.e. multiple threads)?
> > > >
> > > > Does the log switching event occur at approximately the same time?
> > > >
> > > > Rick
> > > >
> > > > Eric Kimble wrote:
> > > >
> > > > > 8.1.7.3.0 on NT 4 system. In looking at the Archived logs I have
> noticed
> > > > > a trend over the last few months. The system will usually switch
> about 3
> > > > > times a day ( not a really busy server) but about once a month the
> > > > > system will go into a hyperactive mode ( I don't have jobs scheduled
> > > > > during this time and it is not the same day each month) where it
> will
> > > > > switch 4-5 time per minute for about 2 hours. I was wondering if you
> all
> > > > > could maybe give me some ideas to check into. I've already looked at
> > > > > Scheduled jobs, I don't have individual users logged into this
> database
> > > > > ( it support a 3rd party app) and the use of the 3rd party app is
> used
> > > > > consistently and hasen't been reported from during those times. It
> of
> > > > > course isn't hurting the system any but I don't like it when things
> > > > > happen on the database and I don't know why.
> > > > >
> > > > > TIA
> > > > > Eric Kimble
> >
> > Log miner as Richard suggests..Also, you could have a logoff trigger to
> > dump out the v$sesstat info which will tell you which session are going
> > beserk with redo
> >
> > hth
> > connor
> > --
> > ==============================
> > Connor McDonald
> >
> > http://www.oracledba.co.uk
> >
> > "Some days you're the pigeon, some days you're the statue..."
>
> Or AUDIT SESSION, maybe?
> Just a thought.
> Paul

I didn't think dba_audit_session recorded redo levels? (although presumably write activity would be a reasonable statistic)

Cheers
Connor

-- 
==============================
Connor McDonald

http://www.oracledba.co.uk

"Some days you're the pigeon, some days you're the statue..."