Scale Up or Scale Out - RAC or not to RAC

[f. halili]

We have Oracle 9i in HPUX 11.11. We are deliberating if we will scale up our hardware or implement Oracle RAC, get entry level servers and scale out when needed.

Any thoughts?

Also when going to RAC do we still use MC ServiceGuard or Oracle RAC will do job that ServiceGuard does?

Thanks,
f. halili

[Oviwan]

Hey

if you go to RAC with asm you won't still use MC ServiceGuard, i believe. but that's on 10g

for more informations check this thread:
http://forums.itrc.hp.com/service/forums/questionanswer.do?threadId=1003578

Regards

[Court Campbell]

If you do 9i you are going to need servicegaurd. if you upgrade to 10g then you will not. This is hard to answer as there is a cost $$ in moving to RAC. Plus the other question is how many servers in a rac installation does it take to perform at the same level if not better than one large box. There are just to many variables to give you a simple answer. I think the rac is awesome, but not for everyone. If you can get a vendor to do a proof of concept that would be the way to go. Just watch out for the sales people, their job is to make money and not worry about your best interests. But that is my opinion.

[Hein van den Heuvel · Accepted solution]

That's a little like asking whether it is better to have a big bus to move a group of folks or whether it is prefereable to use serveral medium cars. It depends!

Do you already have some suitable medium cars? How much synchronization is needed between those cars? Do you want to be able to play cards while traveling? The bus is easier. The cars may be faster and cheaper.

I personnaly like scale out vs scale up for its POTENTIAL to use several smaller & faster(and more cost effective) boxes instead of a single more expensive box.

1) It's just harder to build a good, fast box with more than 4 processors.

2) Instead of the typical 1 active 16 CPU machine at 60% usage + 1 passive machine at 0%, it is nice to have say 4 active machines with 4 cpus at 60% yet be able to run comfortably with 3 out of 4 at 80% load each.
(4*60=3*80=240)

Oracle does a decend job with RAC, but how will it really works for your situation depends entirely on the application usage of Oracle.

Is this for "Oracle E-business Suite" or for SAP? Then be sure to ask Oracle resp SAP about their recommendations/support for a RAC backend.

I'm sure there are plenty of consultants out there (like myself! :-) who are eager and able to help you make the right decision based on your specific situation.

Hope this help a little

Hein van den Heuvel
HvdH Performance Consulting

[rick jones]

Well, in the scale-up arena, the ability to take Oracle to very high levels of TPM-C has been recently demonstrated on a Superdome. (Details at www.tpc.org)

The suggestion to get some professional help in maknig the to RAC or not to RAC question is a good one.

[f. halili]

thanks!