Re: Oracle: how many instances?

I should of course have added CPU

25 instances times say 15 processes for a lightly loaded instance is going to eat pretty heavily into the capacity of two cpu's

--
Niall Litchfield
Oracle DBA
Audit Commission UK
"Niall Litchfield" <n-litchfield_at_audit-commission.gov.uk> wrote in message
news:931hl9$enc$1_at_soap.pipex.net...


> I'm not that familiar with Linux, my experience is mostly NT with some SCO

> (and I'm fed up with the flame wars that comparing to ms always seem to

> provoke) however it would seem to me that you are being somewhat

 ambitious.


>

> There are two key areas thatI would suggest you consider (well actually 3

> but I can't speak with great authority on the third)

>

> Memory.

>

> Your box has 2gig of RAM. allocating 2/3rds of that to 25 instances gives

> according to my calculations just over 50MB of RAM per instance. This is

> unlikely to produce great performance

>

> Disk.

>

> You don't say how many or what spec disks you will be using, but you are

> quite likely with 25 instances to get contention between the instances for

> the same disk resources.

>

>

> The third area is network connectivity, how good are your boxes network

> interfaces and how well will they cope with say 350 simultaneous

> connections?

>

> In addition to all this standard DBA tasks, such as backup and archive log

> management etc will become somewhat more complex with 20+ instances.

>

> regards

>

>

> --

> Niall Litchfield

> Oracle DBA

> Audit Commission UK

>

>

> <bsidba_at_my-deja.com> wrote in message news:9309ei$ti6$1_at_nnrp1.deja.com...

> > Why yes, it is a serious question.  What is wrong with connecting 200

> > to 500 users to a Linux box?  I am relatively new to Linux but I

> > figured that I could get better performance and stability from Linux

> > than NT.  Your input is appreciated.  Thank you

> >

> > In article <93061t$8ajtf$5_at_ID-62141.news.dfncis.de>,

> >   "Sybrand Bakker" <postbus_at_sybrandb.demon.nl> wrote:

> > > 10 to 20 users would mean between 200 and 500 users connecting to a

 Linux


> > > box.

> > > Is this supposed to be a serious question?

> > >

> > > Regards,

> > >

> > > Sybrand Bakker, Oracle DBA

> > >

> > > <bsidba_at_my-deja.com> wrote in message news:92vbj4

 $1bn$1_at_nnrp1.deja.com...


> > > > How many Oracle instances can I run on one server and still have

 good


> > > > performance and reliability?  Each instance will only have about

 200MB


> > > > to 300MB of data and about 10 to 20 users.  The server will be a

 dual


> > > > 933MHz Pentium III Zeon with 2GB of memory running Oracle 8.1.7 SE

 on


> > > > Red Hat Linux 6.2.  I was hoping I could run 20 to 25 instances.  Is

> > > > this out of the question?  I have looked through the forums and have

> > > > been unable to find a similar question and I was hoping that someone

> > > > had experience with this many instances on one server.  Your input

 will


> > > > be greatly appreciated.

> > > >

> > > > Thank you

> > > >

> > > >

> > > > Sent via Deja.com

> > > > http://www.deja.com/

> > >

> > >

> >

> >

> > Sent via Deja.com

> > http://www.deja.com/

>

>