Re: LMT with autoallocate

A copy of this was sent to onlyforposting_at_yahoo.com (Vikas Agnihotri) (if that email address didn't require changing) On 22 May 2001 10:27:01 -0700, you wrote:

>Since HJR doesnt have first-hand experience with autoallocate LMTs, I
>wanted to check if these beasts are used in real-world production
>databases at all.
>
>Could someone who has used LMT (locally managed tablespaces) with
>either autoallocate or uniform extents comment on their alleged
>performance benefits, administrative issues, etc?
>
>Would you recommend LMT over dictionary managed? If so, would you
>recommend uniform or autoallocate?
>
>Thanks...

locally managed tablespaces are (with the glaring exception of system) the ONLY type of tablespace I use. I only use UNIFORM, never autoallocate.

I would definitely recommend them over dictionary managed. space management is a breeze with them (good bye recursive sql). free space fragmentation is a thing of the past -- I always hated pctincrease and with lmt's -- you don't have it at all. SMON doesn't spend half of its life looking for extents that might need coalescing. You never end up with tiny bits of free space that no object will be able to use (they are ALL the same size).

You'll find that you group objects by size and growth into tablespace of various sizes. Do not be afraid (repeat do not be afraid) of objects with dozens or hundreds of extents -- it is really ok.

I have found nothing wrong with lmt's to date.

--
Thomas Kyte (tkyte_at_us.oracle.com) Oracle Service Industries
Howtos and such: http://asktom.oracle.com/
Oracle Magazine: http://www.oracle.com/oramag
Opinions are mine and do not necessarily reflect those of Oracle Corp