Multiple vs. Faster Processors on rp7400

[Michael Geldart]

Hi all,

I was wondering if anyone had done any benchmarking on Multiple Slower procs. vs. a smaller number of Faster procs.
Specifically I am trying to decide whether to buy 1 or 2 550Mhz CPUs for my Dual CPU rp7400 with 3 instances of Oracle 8.1.7.4 (Two of which are Oracle Financials/Applications) or for less money buying 6 360Mhz CPUs for the same Server and moving the current 550s to other servers.

Any Suggestions?

Thanks,

Mike Geldart

[Vincent Farrugia]

Hello,

This depends on the multi-processing capabilities of your application. In this case, although I am no Oracle guru, Oracle can do that.

I would suggest running more processors in this case. It always helps when you have monsters like Oracle. Beleive me; Oracle is VERY resource-heavy, as you have seen... you are upgrading CPUs...

One thing though... if you buy 360MHz CPUs and put them with 550MHz ones... you have to put the bus speed at 360MHz, forcing your 550 ones to run at 360 speed. So it wouldn't be beneficial...

I would prefer if you buy multiple 550 MHz CPUs... you'll need them, considering what you will run...

How is your CPU utilisation anyway? Have you run sar? Measureware is an excellent software with which you can do performance analysis of this type. Also, how much memory have you got? Maybe upgrading memory would be a better solution?

HTH,
Vince

[Alexander M. Ermes]

Hi there.
Running Financials you will need everything you can get ( Vincent is right on that one )
We run Accounts Receivables for 15 production instances. We have approx 300 users working on the different instances. Our version is the old 10.7 char mode. We have a HP V2500 with 12 cpu's ( 550 MHz ) and 12 GB of RAM.
cpu load mostly at 70 percent, peaks ( 1hr ) up to 100 percent. It is not only the databases, which eat your resources like popcorn, it is also the Concurrent Manager jobs.
Did you setup a MTS environment ?
This will help you to bring down the load a little bit.
My personal opinion is to go for 3-4 550 MHz cpu's. This means more processes per cpu, but done much faster.
If i was you, i would contact some competence center of HP or Oracle.
If you need more assistance, just let us know.
Rgds
Alexander M. Ermes

[paul courry]

I agree with the previous respondent, first you should shoehorn as much memory as you can into your box and only then worry about processors. Memory is always the cheapest performance upgrade.

[Leif Halvarsson_2]

Hi
In most cases database applications scales well (can utilize many processors). In this case 6*360 should be better then 2*550. Other applications (for example FEM programs) don't scales very good. A 2*550 configuration will perhaps give nearly the same performance as a 6*360, and a 6 processor license is much more expensive.

[Oleg Khoroshylov]

My suggestions:
1) 4 550 Mhz CPUs will give approximately the same perfomance as 6 360 Mhz CPU's. But buying 550s, it really upgrades system, leaving space for future grouwth.
2) Software licences cost considerations need to be taken into account also. Some soft requires per processor licensing, so with more processors you will need to pay more

BR,
OK

[Michael Geldart]

Hi all,

Thanks for your input.

At the moment our Oracle Finacials usage is low but we are soon implementing a number of new modules which will put much more of a load on the system.

The Current load is an average of about 7% usr and 7% sys according to vmstat.

The issues arise when a user or two sends off an ill advised query or my DBA is applying a patch to the "Patch" database on the same server. In these situations a process will hog a cpu and the production system performance will suffer.

It was my theory that a number of smaller processors would suck up the occasional cpu hog while leaving multiple processors to go about the regular business running the oracle processes.

We have 8GB of RAM in the Server as well as dual "power pathed" Gigabit Fibre HBA's attched to EMC Symm storage so our I/O is healthy.

Thanks again for your comments.

Mike Geldart