New processor PA-RISC8800 dual CPU: How many processors does HP-UX see?

[Romaric Guilloud]

Hello,
The new PA-RISC PA8800 is a dual-core processor available on Superdome.
Assuming I create one n-Par made of one cell (4 processors PA-8800 by cell), how many processors will be seen under HP-UX running on this n-Par.
I was thinking 4, but figured out that IBM with its Power4+ (dual-core processor as well) provides higher granularity by showing the 2 sub-CPUs of the processor as processors themself to AIX.
Got it?
Any link, URL, info highlighting this concern is welcome.
Thank you.

Romaric.

[Mark Grant]

Linux shows 2 CPU's for each dual core too. I imagine it's the sensible thing to do.

[Romaric Guilloud]

Thank you Mark for the hint with Linux on PA-8800,
But how many processors does HP-UX see???

[Jeff Schussele]

Hi Romaric,

Two per core - just as the Itanium does.

I understand that the core could be "split" in vPars but *not* in hard partitions - nPars.

Rgds,
Jeff

[Romaric Guilloud]

So Jeff, in my first example ,according to what you're saying, a "top" command would display 8 processors, right?

[Jeff Schussele · Accepted solution]

Yes - If you have 4 cores in the cell, top *should* show 8 CPUs.
I know that Oracle & their ilk will certainly charge you for 8 CPUs in their licensing, so I'd *hope* that everything else will "see" 8 CPUs.
We don't have any PA8800 systems yet, so I can't verify, but everything I've heard from HP would lead me to believe this is so.

Rgds,
Jeff

[Romaric Guilloud]

Thanks Jeff, I will however cross-check with my HP tech guy next time he's in to get a formal statement on this issue.
Thanks again for your time.
Sincerely,

Romaric.

[rick jones]

Despite Sun's recent quaint attempts to call the UltraSPARC-IV a "single" dual threaded CPU, HP still considers a PA-8800 to be two CPU's on a chip, just as IBM does with their POWER4+ stuff.

If anything, the PA-8800 is at least as much a "dual threaded" CPU as UltraSPARC-IV, perhaps even more so, but HP does still think of it as two CPUs.

In the future, it is probably best to start adding some terms to the vocabulary - for example, considering a cell board to have four sockets, into which one can insert dual-CPU chips etc etc...

Speaking just as myself, if Sun is able to continue to push their "UltraSPARC-IV is a single CPU" agenda, other vendors may need to follow suit.

[Tim D Fulford]

I know this is super late, HP sales guy went to great lengths to stress that the rp7420 (rp7410 replacement) will have 8 SLOTS each slot has 2 CPU's, thus rp7420 will have 16 CPUs.

However on the nPAR front I believe the nPar rules are the same as for pa8700 but replace CPU with SLOT...

I believe this is the same throughout the range EXCEPT at the very lowest where you can still buy a 1CPU (rp34?? I think) system where the 2nd CPU will be switched off (but you still have access to all 32MB L2 cache!!)

Regards

Tim