Re: A performance reason to split up index data files.

Joel Garry wrote:
>
> Kind of interesting non-bug:
>
> http://metalink.oracle.com/metalink/plsql/ml2_documents.showDocument?p_database_id=BUG&p_id=3484607
>
> I wonder how much of this is due to inode locking (as Tanel, I think,
> described in a thread a while ago - Oracle trying to get segments all
> in the same file hitting itself in the nose), and how much is due to O
> coding that assumes non-interfering physical devices for a parallel
> architecture. I don't think the I/O contention explanation is
> correct, wouldn't the max wait be longer? Inode locking on the other
> hand would result in more retries. (I'm assuming there is a typo in
> the second "Index creation with multiple data files" that should have
> said "single data file.")
>
> Moral: Don't expect miracles from SAME. Don't even expect Oracle
> code to work with it rationally.
>
> jg
> --
> @home.com is bogus.
> "Everyone wants to be Cary Grant. Even I want to be Cary Grant." -
> Archibald Leach, AKA Cary Grant.

Direct IO I think resolves the inode issue - maybe this is just Solaris though. Maybe a repeat of the test with the file system mounted for direct IO might provide proof either way.

Cheers
Connor

-- 
Connor McDonald
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