Re: Oracle: how many instances?

You have a lot of good advice from people. At this point you'd have to get more specific. Are you running the standard or enterprise edition? Do you need a Java pool? What sizes are your SGAs? In general, 25 instances would probably be too many for your server. Also, to handle 25 instances on a single server you shouldn't need an assistant if the instances are set up properly to begin with.

Van

<bsidba_at_my-deja.com> wrote in message news:932gn4$odt$1_at_nnrp1.deja.com...
> I wish! Unfortunately the schema name is hard coded in the application
> which is why I have to have separate instances.
>
> In article <932c5h$jud$1_at_nnrp1.deja.com>,
> steveee_ca_at_my-deja.com wrote:
> > Hi,
> >
> > Is there a possibility to create schemas within instances instead of a
> > whole new instance for each group of users? If so, you can cut your
> > demand for resources..
> >
> > Steve
> >
> > In article <932205$a6c$1_at_nnrp1.deja.com>,
> > bsidba_at_my-deja.com wrote:
> > > Thank you so much for your reply. I realize that 25 instances with
 the
> > > configuration below is a little ambitious. Truth be known, I will
 more
> > > than likely stop at around 15 to 20 instances and marketing is
 telling
> > > me that many of the instances will have 5 or less users.
> > >
> > > You are right about the memory. I had actually already told them
 that
> > > I would need 4GB of RAM to support that many instances which still
 is
> > > not ideal but I am planning on creating small SGA's for some of the
> > > smaller instances with 2 to 3 users.
> > >
> > > The system will have 17 to 18 disk drives (5 arrays of RAID-1 so I
 will
> > > actually have about 11 to 12 drives to work with). This will allow
 me
> > > to totally separate tablespaces, logs, etc. and therefore eliminate
 any
> > > I/O contention within an instance. However, I will have I/O
 contention
> > > between the instances. I am running the same drive configuration on
> > > our development machine and have not noticed any performance
 problems
> > > however, the number of users on this development machine is
> > > significantly less than I am planning for this new machine.
> > >
> > > I have spoken to the network guys and they don't seem to be real
> > > concerned about the network traffic. And regarding the DBA task, it
 is
> > > my understanding that I will be getting an assistant soon (I hope!).
> > > However, you raised a good point about the processes. I will be
 doing
> > > some more research into that.
> > >
> > > Based on everything I have said above, do you think that I am still
> > > reaching or is 10 to 15 instances all that I can really hope to run
 on
> > > this server? Thank you again for your reply and any more
 information
> > > that you or anyone else can supply will be greatly appreciated.
> > >
> > > Thanks
> > >
> > > In article <931t8h$klc$1_at_soap.pipex.net>,
> > > "Niall Litchfield" <n-litchfield_at_audit-commission.gov.uk> wrote:
> > > > I should of course have added CPU
> > > >
> > > > 25 instances times say 15 processes for a lightly loaded instance
 is
 going
> > > > to eat pretty heavily into the capacity of two cpu's
> > > >
> > > > --
> > > > Niall Litchfield
> > > > Oracle DBA
> > > > Audit Commission UK
> > > > "Niall Litchfield" <n-litchfield_at_audit-commission.gov.uk> wrote in
 message
> > > > news:931hl9$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/
> > > > >
> > > > >
> > > >
> > > >
> > >
> > > Sent via Deja.com
> > > http://www.deja.com/
> > >
> >
> > Sent via Deja.com
> > http://www.deja.com/
> >
>
>
> Sent via Deja.com
> http://www.deja.com/
Received on Thu Jan 04 2001 - 18:48:49 CST