Re: Rman issue
- From: Dennis Williams <oracledba.williams@xxxxxxxxx>
- To: arunrao_oradba@xxxxxxxxxxx
- Date: Mon, 11 Jul 2005 16:42:27 -0500
Arun,
Let me see if I understand your problem. You feel RMAN is using too
much I/O, and you want to reduce that? I'm assuming that RMAN is not
leaving enough I/O for other processes that are running at the same
time? You tried reducing the channels to 4 since you have 4
controllers?
What are you writing the RMAN backups to -- disk or tape? Usually
the target system is what limits the I/O, and usually that limitation
is a problem, not the source disk system.
If RMAN uses less I/O, it will take longer to complete, which will
extend the contention with other processes. Perhaps you can rearrange
the competing processes in terms of time to experience less
contention.
My guess is that you should try fewer channels than controllers in
order to reduce RMAN's I/O rate. You probably need to reduce the
number of channels below 4, to 3 or 2.
I have not used the diskratio parameter, perhaps someone else on
the list has.
Dennis Williams
On 7/11/05, arun chakrapani rao <arunrao_oradba@xxxxxxxxxxx> wrote:
> Hi gurus,
> Has anybody used diskratio parameter in rman, if so
> have u seen any benefits using that
> I am seeing a very high io used by rman here on a prod
> box which is running on hp itanium.
--
//www.freelists.org/webpage/oracle-l
Other related posts:
