What is the maximum extent size possible in locally managed
tablespaces (LMT) with autoallocate?
Let me clarify the question: I am interested in conventional datafiles
(not bigfiles).
I understand that "strictly speaking" this question does not have an
answer as
extent allocation in LMT isn't do***ented by Oracle and can change
between versions/platforms/patches, may depend on block size,
datafile size, empty space, etc. So I am looking for "informal" answer
applicable in real life.
In my tests (done with 8K block size) max extent size was 64M, even
for 20 GB table.
I saw this value mentioned in several discussions, although Jonathan
Lewis mentions 256M:
http://www.jlcomp.demon.co.uk/faq/lmt_losses.html
Why do I need an answer: we have several databases that were created
with 20+ filesystems,
50+ tablespaces, many tablespaces between 1GB and 3 GB, and with
random distribution of datafiles between filesystems. Now the
filesystems are 98% or so full, AUTOEXTEND has been disabled,
and I need to monitor next extent size as extent allocation in an LMT
can fail even when tablespace has 15% free space.
Thanks
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