We share a single database home among many instances on the same server but don't have this problem. When we need to patch, we clone to a new home and apply the patch there. Then "patching" the databases is a simple as a quick restart on the new home (and running the patch script if there is one). Much of this is scripted in our environment. The "sheer cost of maintainance" is IHMO a good argument for shared homes in large environments. Every copy of the binaries is another copy that you have to maintain. But I think that the dedicated homes model is a little more developed and widespread right now, so in a smaller environment I'm not sure I'd move away from it. I think the privilege separation is probably a rare requirement, but you'd definitely need separate homes for it. Actually we're also exploring the NFS idea right now too. We're developing some interesting ideas around having the ORACLE_HOME on a readonly NFS mount. -Jeremy Mark W. Farnham wrote: > > Matthew makes an excellent point about allowing freedom in the update > rythym by database and application. While in very high count database > sites I worry about the sheer cost of maintenance to have every > database in its own home, that can be workable with automated update > systems where the human dbas only need to deal with exceptions. > Without automation you still need at least a few. Three or four for a > dozen or more databases can often work out as a sweet spot, as long as > you’ve got a good way to move a given database from home to home. > Likewise, the likelihood of different update rhythms between > applications is a good reason to think seriously about putting them in > separate databases. > > > > Regards, > > > > mwf > > > > ------------------------------------------------------------------------ > > *From:* oracle-l-bounce@xxxxxxxxxxxxx > [mailto:oracle-l-bounce@xxxxxxxxxxxxx] *On Behalf Of *Matthew Zito > *Sent:* Thursday, May 14, 2009 5:44 PM > *To:* sims@xxxxxxx; Oracle-L Freelists > *Subject:* RE: Oracle installation on Local disk vs. SAN > > > > > > I have both extremes - customers with 100+ instances running out of > one ORACLE_HOME, and customers that deploy one ORACLE_HOME for every > instance. We typically recommend the latter configuration, especially > for production environments, as it removes the, "Well, I don't want > you to apply that patch to *my* database" coupled with "But I *have* > to get that patch applied to *my* database" between two users sharing > the same oracle_home. > > Plus it allows you to do better privilege separation by running > different databases as different OS users. > > Thanks, > Matt > > -- > Matthew Zito > Chief Scientist > GridApp Systems > P: 646-452-4090 > mzito@xxxxxxxxxxx > http://www.gridapp.com > > <snip> > -- Jeremy Schneider Chicago, IL http://www.ardentperf.com -- //www.freelists.org/webpage/oracle-l