Itanium Performance Question

[Doug_3]

Hi all, we have been on an ancient HP9000 7400 4way platform. We are interested in the performance characteristics of the Itaniums. It is hard to compare cpu and bus of one to another so I am looking for good links or advice.
I've checked the white papers which glowing tell of great performance, but trying to compare the rp 3600 or 6600 to our venerable old box is a bit tough. Our real goal is to determine which of the rp and cpu mix is the correct match to our business needs.

We run an ERP app and informix db server on the same box. We are thinking of the rp3600 2 way with dual cores and try to dump as much memory as we can afford into it.

Thanks in advance,
Doug

[Tim Nelson · Accepted solution]

To cross compare same vendor equipment you can look at the TCP results although I doubt that the entry-level 3600 will be on there.. tcp.org the numbers may be BS but at least when comparing the same vendor you should be able to use it as a %.

Another option is to ask your HP re-seller to provide you with the answers. Make them work for their money.

Compared to the old N4000, even the entry level rp3600 should be able to blow that away. Now-a-days the procs seem like they are all the same. The real question is how much expansion do you need, or how many IO slots do you need.

[TwoProc]

Doug, in going for a PA-Risc 7800 to the newest Itaniums, HP is using an estimate of 2:1. You're way back on 7400, which is what speed - 440 Mhz maybe? Anyway, from what I can decode from that, then a 2 way theoretically more than covers the job. BUT! What it doesn't cover is that your running jobs would have only two CPUS to run on, instead of four. So, let's say you used to have a couple of jobs that ran 1 hour each that run at the same time - this left you with two free CPUs to do whatever else it took to run the group's needs. And, let's say you're 3 times faster - so those two reports now only take twenty minutes each. Well, the problem is, that if they both ran at the same time - you're out of luck, and will not run well at all. Now, that's a simple example, but I think you get the idea. With a 2 proc system, you can only afford to have a single long running job while the rest of the company has to basically run in the other one, even though, *when not overloaded*, the new server is 3 times faster.

So, while total CPU horsepower is a good metric, don't forget to factor in work-divisibility for handling long running jobs, batches, queues, etc.

[rick jones]

Various nits:

The Itanium systems have model names starting with "rx" not "rp." The current HP 9000's have model names starting with "rp." So, it would be the rx3600 and the rx6600, and depending on how much and what sort of I/O you had in the 7400 the rx2660 that might be of interest. If you were replacing more than one rp7400, another possibility would be either the BL860c or BL870c in a c7000 blade chassis. The shortcut to external writeups of a given Integrity (or HP 9000) system would be:

http://www.hp.com/go/

eg

http://www.hp.com/go/rx3600

I think Tim meant to say TPC rather than TCP, although to my netperf-addled mind I suppose you could compare TCP performance if you liked :)

Rather than TPC (or TCP) I suspect an HP Sales contact could give you some relative performance information, which would be an amalgam of a number of performance measures.

[Bernhard Mueller]

Doug,

usually when you do such a migration you also upgrade software versions, which tend to consume more resources. Ask your software vendor. If you will be still running Informix 9 and just re-compile the ERP application for Itanium, I'd side with Rick and suggest that even an rx2660 might be sufficient. But do not forget that this is a platform change and you should use native binaries compiled for Itanium if performance matters.

Regards,
Bernhard