Re: What is Parallel DML?

"Howard J. Rogers" <howardjr_at_www.com> wrote

> Read Jonathan Lewis' post on the subject, and you will see that
> my argument is not nonsensical, nor wrong-headed, nor circular.

Jon simply described the pros and cons of PQ. As I recall, you specifically said that PQ is pointless on a single CPU platform. And that is what I've taken exception too as that concept _is_ an old wife's tale that rears its head in this newsgroup every so often.

> Arrogant shits who refuse to look facts in the face annoy me.

I may come across arrogant Howard, but PQ is one thing about Oracle that I do know something about. And unlike you, my experience is not from a couple of simplistic experiments, but from a couple of years looking after an OPS warehouse on a MPP cluster where each cluster node was a single CPU box.. and we were running PQ on each node. To get technical - back then, each node was a single MIPS R4000 200Mhz CPU running Reliant Unix and Oracle 7.3 (and then 7.4). I found that 8 to 10 PQ's per node gave me the best CPU utilisation. Unlike on a Intel MMX 200Mhz NT platform running Oracle 7.3 (or was it 7.1) and NT 3.5 - my state-of-the-art little R&D box at time, where anything more than 2 to 3 PQ's started to throttle the CPU. But even there, using 2 PQ's doing a FTS resulted in significantly faster performance, than using a single process instead.

PQ pointless on a single CPU platform? Think again.

--
Billy