Re: should initial = next?

The general advice now is

create tablespaces with uniform extent sizing do not allocate storage per segment.
eg

128k tablespace , 4mb tablespace, and so on rising by an order of magnitude each time.

then store segments in the most appropriate tablespace. so for your example you'd probably store your 900mb table in a tablespace with 4mb extent sizes. The point is that all segments in that tablespace have the same extent size, so fragmentation will no longer be an issue. If you have 8i then you will probably want to ensure that you use locally managed tablespaces as well so as to avoid excessive data dictionary operations when allocating extents to segments.

--
Niall Litchfield
Oracle DBA
Audit Commission UK
"Steve Salvemini" <steve.salvemini_at_adelaide.edu.au> wrote in message
news:3A7F20CF.D707C57_at_adelaide.edu.au...


> Hi, I've read recently of the importance setting the initial extent size

> and all next extent sizes to the same value, and that the overhead of

> for eg 1000 extents is insignificant compared to the gains [Dave Ensor -

> BMC Software]

> (I hope I'm reading this right Dave!)

>

> Anyway, as an example, if I've got a table of 900Mb, currently we are

> setting:

> initial extent to 900Mb

> next entent of    256K

> max extents       400

>

> From reading this article, is it better to have a setting something like

> initial extent to 1098 K

> next entent of    1098 K

> max extents       1000

> (ie 1098*1024 * 600 extents = 900Mb, leaving 200 extents free (=200*1098

> =  219Mb for growth))

>

> Is it generally accepted out there that this is a better approach or is

> this splitting hairs (or did I totally misunderstand this) ?