6 disks? An EMC array can throw 20x as many physical disks at this sort of problem. An Exadata can compile SQL down to microcode and execute it on the storage, like a graphics card doing matrix operations on dedicated hardware.
Again, as I say, the NoSQL crowd have no idea about what the state of the art is in the RDBMS world.
it's awfully hard to even fit 10TB on a RAID1+0 setup
It would actually be hard for me to buy an array that small...
I have a pretty solid idea what state of the art is in the RDBMS world - it's diminishing returns as a machine that's twice as powerful costs 10X as much, all the way up the enterprise ladder. It's spending 100k on your software licenses, 100k on your storage and 500 bucks on a CPU.
Not that there's anything wrong with that. It's ok. If your domain is highly transactional, it's probably a better move than implementing your own transactions over something else. Just don't pretend that your limitations are actually strengths -- you have your own strengths.
It doesn't matter. You see, in business, there is no "cheap" or "expensive". There's worth the money, or not. It doesn't matter how many commodity servers I could buy for the cost; no matter how cheap they are, the money would be wasted if that simply the wrong technical approach.
Because you can't compete at this level by chucking increasing amounts of anything at the problem - people, dollars, spindles, nodes, you name it.
You see, in business, everything is about cheap or expensive. It's just a more broad definition that includes developer time and ROI.
If your problem is extremely transactional and legitimately unshardable, feel free to drop 6 mil on exadata. Or a half a mil on a database server and backup. But frankly, your objections are starting to have a religious feel to them. All I was saying is that PL/SQL is a pile of crap to code in and fundamentally unscalable without spending a boatload of money. A little better design can get the same thing with a lot less cash.
EDIT: No, those are facts, PL/SQL looks like it was designed in 1965 and, yes, putting all of your CPU processing into a single node is fundamentally unscalable. I've seen it. It was fundamentally unscalable.
I'm not making a religious point about RDBMS - it can be the best model in many situations. I'm making a point about single bottlenecks for your architecture.
You buy the EMC unit, because you want the EMC tech to call you and say "we see you have a failing drive, I'm en-route, and I'll be there in 15 minutes with a replacement". Even if you are not paying attention, the unit called in and told the control center it needed attention.
Again, as I say, the NoSQL crowd have no idea about what the state of the art is in the RDBMS world.
it's awfully hard to even fit 10TB on a RAID1+0 setup
It would actually be hard for me to buy an array that small...