Re: Extent Allocation among Multiple Datafiles ?

I have no comment on your message. But I did a string search from my d:\orant\doc downward for the string "robin". 21 files are found. Some of them are idx files (documentation index, binary files). Of all the 14 htm files, none of them is talking about round-robin space management, unfortunately. "Round robin" is used in dbms_repair, create consumer group, plan_table.distribution, partition assignment in OPS etc.

This is documentation 8.1.5.

Yong Huang
yhuang_at_indigopool.com

Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk> wrote in message news:968521406.12173.0.nnrp-08.9e984b29_at_news.demon.co.uk...
>
> I've just run a few tests of this with locally managed
> tablespaces, usng the 'alter table allocate extent'
> command, and the algorithm certainly seems to be
> a round-robin. I vaguely recall seeing something in
> the manuals to this effect too, but can't find it at
> present (isn't that always the way).
>
> There is no visible clue in the recursive activity
> to prove that Oracle is doing a round-robin, other
> than the fact that Oracle loads the file$ details
> for all the files in the tablespace as the first
> step of allocating the extent. Presumably the
> actual decision code is hidden in dictionary
> cache processing of dc_used_extents.
>
> --
>
> Jonathan Lewis
> Yet another Oracle-related web site: http://www.jlcomp.demon.co.uk
>
> Jonathan Lewis wrote in message
> <968435216.19084.0.nnrp-12.9e984b29_at_news.demon.co.uk>...
> >
> >It's just occurred to me that the apparent round-robin
> >may be a side-effect of the way space management
> >works on dictionary managed tablespaces and not
> >a planned feature. I'm going to have a proper look at
> >it, and will get back to you.
> >
> >--
> >
> >Jonathan Lewis
> >Yet another Oracle-related web site: http://www.jlcomp.demon.co.uk
> >
> >
> >
>
>
Received on Mon Sep 11 2000 - 13:31:59 CDT