Re: new DirectX Oracle online monitor

"Boaz Laufer" <lauferb_at_adit-tec.com> wrote in message news:1bacd337.0403300005.5de44e21_at_posting.google.com...
> joel-garry_at_home.com (Joel Garry) wrote in message
news:<91884734.0403231611.28680743_at_posting.google.com>...
> > lauferb_at_adit-tec.com (Boaz Laufer) wrote in message
news:<1bacd337.0403220958.799a765f_at_posting.google.com>...
> > > Hello DBA's,
> > > I'd like to invite you to my site to try my new DirectX based oracle
online monitor.
> > > The name is 'SGAgent'.
> > >
> > > http://boazl.com
> > >
> > > Regards,
> > > Boaz.
> >
> > Why would you want to compress extents? Why would you want to use
> > something based on Direct X? What does this have that OEM doesn't?
> > What is SGAgnet [sic]?
> >
> > jg
>
> Rebuilding database objects improve performance!
> I checked it a lot of times and it improves performance a lot.
> There are some reasons why this improves performance:
> Rebuilding database Objects:
> * Empties the Free-Lists.

Which is not necessarily such a brilliant move if your table is about to be subjected to new inserts such that it has to re-acquire the space that your rebuild caused it to lose, but which it already originally had.

> * Fix Chained rows

Nothing can fix a chained row except for the re-creation of the database. You are talking about row *migration*, not row chaining.

> * Compress the data inside the blocks (saves space and Cache-Memory)

And increases the chances of user-collisions on a well-packed block and thereby increase your chance of getting buffer busy waits.

> * Rebuild the indexes - makes them more balances

Oh God. Indexes in Oracle are ALWAYS ALWAYS ALWAYS balanced. Automatically. In real time.

I don't mean to be unkind, but you appear to be lacking a little in the 'there's more to this than meets the eye' department. Sometimes an object re-organisation might be beneficial. And sometimes it will make no difference. But all times, there will be massive I/O costs and locking issues. So you have to weigh these things up carefully on a case by case basis, and you can't just blunder about with a sackfull of myths, half-truths and complete misunderstandings to see you on your way.

Regards
HJR Received on Tue Mar 30 2004 - 03:31:03 CST