rx2660 vs. rx3600

[Scottt]

I'm looking to get advice on comparing these 2 servers. Outside of the obvious of ram capacity, PCI slots and physical height, if I want 4 cores and 16 GB of ram on a server is there any reason to go with the rx3600 over the rx2660? The salesman is telling me the rx3600 will get 20% better performance (of course more expensive as well) because it's a newer chasis. The system bus bandwidth, the memory bus bandwidth, the chip set, etc is the exact same. Any kind of speed or tps test results I've found with simliar hardware between the 2 say they're the same. Should I expect the same performance between these 2 models running HP-UX 11i v2 (or v3) running an Oracle DB?
Any advice or first hand knowledge is appreciated.

P.S. This thread has been moved from HP 9000 to Servers > Integrity. -HP Forum Moderator

[Duncan Edmonstone]

I suspect the 20% better performance is based on the fact you can put more memory in the rx3600 (certainly helps for most loads). As you have surmised, chipset-wise these systems are effectively the same.

I could be wrong but for rx3600 and rx2660 with the same number of CPUs, memory and IO configuration, I don't think you would see any difference.

I would expect better performance with 11iv3 than v2 for a number of reasons - there are plenty of optimisations in the OS code (not least being it can take advantage of hyperthreading on the Montecito processor)

So if you *really* don't need the memory and IO scalability, the rx2660 looks like a good bet.

HTH

Duncan

[Scottt]

I appreciate the response. The v3 info is definitely helpful, although I didn't find nor did the vendor a part number to order v3 even though it's listed as an available OS for it.

[rick jones · Accepted solution]

The salesman is probably slightly confused between the rx2660 which is a new chassis, and the older rx2600 and rx2620's, which are an old chassis.

The rx2660 and the rx3600 are both based on the "zx2" chipset. I do not recall if they run all their busses at the same speed, but I believe there are some SPECcpu2006 numbers (SPECcpu2000 is obsolete) posted for the both of them. Caveat - if they aren't using the same compilers and patches that may skew the comparison.

In broad handwaving terms, while they may not have all released at the same time, the rx2660, rx3600, rx6600 and the BL860c are all of the same generation.

[Thomas J. Harrold]

I recall the rx3600 has the option for a PCI-Express backplane, rather than the PCI-X backplane. This means higher I/O bandwidth, so you can more effectively use multi-function cards, quad cards, etc.

That plus the newer chipset should keep this a viable box for the next 5-7 years. I've noticed that the cost delta is about $7k for a similar configuration. (rx26xx vs rx36xx)

-tjh

[Torsten.]

Hi,

don't mix up the lagacy rx2600 and rx2620 with the new rx2660.

Even the rx2660 can have pci express slots.

http://h20341.www2.hp.com/integrity/cache/452201-0-0-0-121.html

The advantage of the rx3600:
- more memory
- more I/O

Of course, more memory may result in better performance ;-)

[Scottt]

Thanks for your input.