Re: LMT and DMT

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Wed, 5 Feb 2003 21:37:51 -0000
Message-ID: <b1s0ff$hv8$1$8302bc10@news.demon.co.uk>

Here's a dinky little joke -
Checked on 9.2.0.1 so far.

If your system tablespace is an LMT,
every tablespace has to be an LMT, except for transported DMTs which have to be
permanently read only.

So why does smon STILL run a query
every five minutes to see if there are
any dictionary managed tablespace
with free extents that could be coalesced ?

--
Regards

Jonathan Lewis
http://www.jlcomp.demon.co.uk

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Richard Foote wrote in message
<8iP_9.38221$jM5.96585_at_newsfeeds.bigpond.com>...


>

>The Concepts and Administrator's manuals discusses this in some

depth.


>

>Basically DMT store extent and free space info in the data dictionary

>causing possible performance issues and stress on the dd, and extents

can be


>of any size causing possible fragmentation problems.

>

>LMT store extent info in a number of bitmap blocks within the

datafiles


>themselves resulting in a stress free dd, faster

allocation/deallocation of


>extents and can be configured with a uniform extent size resulting in

no


>fragmentation issues.

>

>LMT is better.

>

>Cheers

>

>Richard

>

>

Received on Wed Feb 05 2003 - 15:37:51 CST