Re: Oracle: how many instances?

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

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