Single instance vs Multiple instances Geodatabase setups for Oracle

[MoizIshfaq]

Greetings all,
Please share your opinion regarding the pros and cons of having either multiple instances or a single instance of ArcSDE in Oracle for production data. Our data size is about 35 GB right now and it is growing on a yearly basis. It is experiencing an average transaction rate of 1000 spatial / attribute changes in a day.

The questions I am interested interested in are:
1.   Is there any impact on the performance?
2.   How much maintenance effort is added since arcsde administration work is distributed to the schema owners?
3.   Any other pros and cons details?

Thanks in advance.

[MoizIshfaq]

Hello,
I found this link 'http://forums.esri.com/Thread.asp?c=2&f=1719&t=170925#503551' while searching this forum and found it helping so I am sharing it here.

Thanks.

[VinceAngelo]

That link is to a discussion about SQL-Server.  There is a great deal of difference between
single vs. multi-database administration in SQL-Server and user geodatabases in Oracle.
Mostly the difference is between the way the RDBMSes are architected, allowing true
independence between SQL-Server databases in a single server, and the false sense
of independence fostered by user geodatabases in Oracle. 

If I want independence with Oracle, I set up multiple SIDs.  This allows me to have different
versions of ArcSDE in different instances, simplifies the backup/restore situation, and allows
easier control of the resources allocated to the different databases.

- V

[SteveSalas]

We have a few of these geodatabases and I would agree with Mr. Angelos recommendations.  They work fine for some small projects when we need multi-user versioned editing for a limited duration and we know that the final archive will be just a file geodatabase.  I don't even want to think about what would happen with long-term use when upgrading SDE versions when there are possiblely different client (Desktop & Server) versions needed, or the version dependencies created by replication.
-S.Salas