The paper I linked to seemed to suggest that they weren't using async IO
in 9.2 -- which is fairly old. I'm not sure why the authors didn't test
10g.
  
...<reads paper>... ok, interesting. Did they say that Oracle isn't using aio ?
I can't see that. They that Oracle has no more than one outstanding I/O
operation in flight per concurrent query,
and they appear to think that's a bad thing. I'm not seeing
that myself. Perhaps once I sleep on it, it'll become clear what they're getting at.

One theory for lack of aio in Oracle as tested in that paper would be that they
were testing on Linux. Since aio is relatively new in Linux I wouldn't be surprised
if Oracle didn't actually use it until it's known to be widely deployed in the field
and to have proven reliability. Perhaps we've reached that state around now,
and so Oracle may not yet have released an aio-capable Linux version of their
RDBMS. Just a theory...someone from those tubular towers lurking here
could tell us for sure I guess...






Reply via email to