Re: Which RBS is my Update using ?

Hi Brian,

But the use of OPTIMAL is the issue.

Daniel's methodology is such that he prefers *not* to use the SET TRANSACTION USE ROLLBACK SEGMENT large (for the reasons he's stated) and *not* to use OPTIMAL (for the potential performance issues of extents being deallocated during a transaction).

Paul's methodology is such that he also does *not* want to use OPTIMAL because of the possible performance issues but *does* prefer to use SET TRANSACTION USE ROLLBACK SEGMENT large for his few but pricey large transactions such that the majority of his ordinary small transactions can use smaller, non optimal constrained rollback segments.

Note there's another current thread 'Optimal size for rollback' where the pros and cons of optimal are being debated.

My methodology is that it depends so I can just sit back and watch the battle unfold ;)

Cheers

Richard
"Brian Peasland" <oracle_dba_at_peasland.com> wrote in message news:3D9061BE.B41C13FB_at_peasland.com...
> > Daniel,
> >
> > Why should they all be 1 gig on a read-only database?
> >
> > Paul
>
> You don't define them *all* to be 1-GB. You only define them to be able
> to *extend* to 1-GB. Then, make sure you set OPTIMAL so that the one
> rollback segment that does extend will shrink back to a smaller size.
> This way, you don't have to set your transaction to use one particular
> rollback segment. No matter which one it grabs, it has the capability to
> expand any of the rollback segments to a large enough size.
>
> HTH,
> Brian
Received on Tue Sep 24 2002 - 08:39:42 CDT