Re: Oracle question from a Sys. admin, re: Solaris performance

tonij67_at_hotmail.com wrote:
>
> Hi all,
>
> Let me preface this by stating that I am not a DBA, so please take what
> I say with that in mind.
>
> I support several Sun systems running various versions of Oracle; 8,
> and varients of 9. We are in the process of getting them all to 9.2
> but there are still some hangers-on at 8.
>
> I have been interested in learning as much as I can about Oracle as it
> may help in supporting the hardware and OS. I have been scouring the
> net for information about performance and found asktom.oracle.com ...I
> found an article that jumped out at me, about running 4 instances of
> Oracle on a system and getting poor performance. This interested me
> because we have upwards of *50* instances on a single machine with more
> on the way. Thats not a typo, 50 as in fifty.
>
> The article I looked at basically said that supporting 4 instances
> would be a "nightmare" because you never know which instance is taking
> resources. I have a couple questions about this:
>
> - is this true? Is there really know way to determine which instance
> is using, say 99% CPU?
>
> - are we insane for having this many instances on a system? I think
> its the result of sale and marketing gone wild...
>
> TIA,
As you've seen from other posts, there may be the risk of performance issues as various instances possibly compete for resources, but obviously, if your machines are high enough spec'd then things might be just fine.

My only contention with that many database/instances is a different kind of risk - that of human error. If all the databases could be consolidated into (say) a single database, then (theoretically) its less backup mechanics, less maintenance of things that are possibly common (user accounts, some tablespaces etc), less distributed maintenance for where those systems need to talk to each other etc.

But, if you've got all that in hand, then I don't see any need for you to change. Maybe just change the mindset... each application or set of them, does not by *definition* need a database.

hth
connor

-- 
Connor McDonald
Co-author: "Mastering Oracle PL/SQL - Practical Solutions"
Co-author: "Oracle Insight - Tales of the OakTable"

web: http://www.oracledba.co.uk
web: http://www.oaktable.net
email: connor_mcdonald_at_yahoo.com


"GIVE a man a fish and he will eat for a day. But TEACH him how to fish,
and...he will sit in a boat and drink beer all day"

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