Re: Extent Allocation among Multiple Datafiles ?

Steve,

I think that this is another of those 'little things' which Oracle has improved over time without getting round to mentioning it as a feature in the manuals.

I have just run a quick series of simple tests in 8.1, and been unable to break the cycle by leaving isolated free extents of exactly the right size in the 'wrong' tablespace. It is still possible, of course, that more complex situations would result in undesirable behaviour; and I am fairly sure that I have seen some examples in Oracle 8.0.4 which were less precise.

--

Jonathan Lewis
Yet another Oracle-related web site:  http://www.jlcomp.demon.co.uk

Steve Adams wrote in message <39bd33a8.659598442_at_nsw.nnrp.telstra.net>...


>Hi Jonathan,

>

>I believe that round robin extent allocation was at first only used for

 parallel


>segment creation operations, but was implemented for dynamic extension in

 7.3.


>However, from some testing I did at the time, it seemed that Oracle would

 reuse


>an extent of the correct size in any datafile rather than split an extent

 in the


>"next" datafile.

>

>@   Regards,

>@   Steve Adams

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>@

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>