Re: 30 instances on one host

Alan wrote:
>
> For example, OFA asks the DBA to place software on a mount point
> separate from the data mount points. The faulty logic behind this is
> that it will separate I/O and thus boost performance. The truth is
> that the software mount point will generate relatively little I/O; the
> software mount point would be quiet and the data mount points would be
> busy. So, a DBA following this advice would not optimize the I/O
> potential of the host.
>
> The OFA advice on mount points also holds little water when viewed
> from the perspective that on most decent sized UNIX boxes, I/O
> spreading is now done inside the storage array. The days of having a
> mount point logically connected to a disk partition's address are
> gone. OFA was written for systems built before the proliferation of
> disk volume management software like Veritas.

This is not accurate. OFA is designed to address managability of Oracle isntallations by providing guidelines for naming conventions and the like. It is not designed to address performance. The reason to separate Oracle software is not for performance, but for managability.  

> One bad naming convention in OFA is this:
>
> If you install an OFA-compliant Oracle Server, the Oracle home
> directory is
> $ORACLE_BASE/product/release_number.
>
> The above convention restricts the DBA from running 2 instances (or
> 30!) of the same release on one host.

Only if you assume each instance must have its own code tree. But you can certainly run more than one instance per code tree.

That said, the reasons for running so many Oracle instances on the same host are few and far between. I can only think of one organization in our company that can justify such a configuration: training, where each member of the class needs his or her own database for the exercises.

Regards,
Sean Received on Mon Jun 17 2002 - 23:01:17 CDT