Comments embedded.
Regards
HJR
--
Oracle Resources : http://www.geocities.com/howardjr2000
========================================
"Prem Alleppey" <prem_alleppey_at_yahoo.com> wrote in message
news:bf7b9060.0110311411.560493bc_at_posting.google.com...
> We are looking into using Oracle Standby for disaster recovery for an
> OLTP database and would like to keep the potential data loss to be
> about 5 minutes worth.
>
> A couple of questions in this regard, especially from those who use
> Standby for DR:
> * If we force log switching to happen every 5 minutes, what would be
> the performance impact of that?
Disastrous.
>Would it be significant or negligible?
Significant
> What would could we do to minimize the impact?
Nothing. Just don't go there, OK?
> * How much time does the ARCH process take to archive the files once
> the switch happens? What can we do to make sure that ARCH is not
> lagging behind?
>
Have a billion and one online redo logs? Look -it's a *really*, *really*
bad idea. Standby databases give you a *level* of security, but not that
sort of level! If you want that degree of protection from data loss,
consider Parallel Server or replication strategies.
Better yet, upgrade to 9i, where Data Guard really can give you the 5 minute
level of protection you're after, policed, resourced and with potentially
huge impacts upon the availability of the production database.
Don't do it. Please!
Standby databases are designed to be the current redo log behind the
production database. You start adjusting your redo log sizes to translate
that into a 5 minute lag, and you are looking disaster squarely in the eye.
Checkpoints are awful affairs for performance. You'll be having one every 5
minutes. It doesn't bear thinking about.
Regards
HJR
> Thanks in advance..
Received on Thu Nov 01 2001 - 02:56:20 CST
