Re: 30 instances on one host

On Thu, 20 Jun 2002 05:54:40 GMT, joel-garry_at_nospam.cox.net (Joel Garry) wrote:

>On Tue, 18 Jun 2002 04:01:17 GMT, Sean M <smckeown_at_earthlink.net> wrote:
>>Alan wrote:

<snip>>
>I can additionally imagine a large org having a huge machine with a bunch
>of different depts with their own instances, for various reasonable reasons.
>(Not to mention unreasonable reasons, but I won't go there). I agree that
>it would be pretty rare. Although, doesn't IBM run machines with thousands
>of individual linux (linices?)...
>

It's been a few years since I've been involved with IBM mainframes, but when I was, their VM (Virtual Machine) operating system was regularly used to run multiple versions of their MVS (Multiple Virtual Storage) operating system, thus creating (voila!) multiple virtual machines on one physical box. And this was nearly 20 years ago on what was then considered to be a small to middling size machine in IBM's lineup. Given that mainframe technology hasn't exactly stood still while Wintel has slowly been re-inventing the wheel, I can quite easily see running several to many (you define "several" and "many") Oracle instances/databases on the right hardware.

Only slightly off topic: A couple of years ago we were working on a new web based app that needed access to data on Oracle and DB2 databases and were using database links and the Oracle Transparent Gateway to get to the DB2 tables. After working with this for a while I asked why we didn't simply put all of the data on DB2. One of the hired consultants (a young MCSE) asked in all seriousness if I thought the mainframe could handle the load . . . .

Of course, he WAS young and his entire lifetime experience with computers had been defined by Wintel.

--
Ed Stevens
(Opinions expressed do not necessarily represent those of my employer.)