9111-285 - New to POWER5

[MDBenson]

Wasn't sure where to post this, so put it here as it's more genreal hardware oriented than AIX... in parts.

Thanks to a very generous eBay seller, I am the proud owner of a (was) new-in-box IBM Intellistation 285 (9111-285) workstation. I've dabbled with RS/6000 and AIX 5L before on a 7046-B50 but have always wanted a really top-drawer IBM machine to work with and this came along at frankly a silly price. Couldn't turn it down. I am a hobbyist purely on IBM machines, I don't have any professional training or expertise on IBM hardware, just the few nuggets I've learned myself so excuse me if I seem a bit clueless. One only learns through doing!

I'm still getting used to the machine's IBM idiosyncracies but we're getting along together so far. I have some questions, however...

 = 'top' in Debian and 'topas' in AIX 5L both show CPU0 and CPU1 and Debian is running a SMP kernel. Is this representative of a Single Core, 2 Thread POWER5 ofr a true Dual Core POWER5. The machine was sold as a 1.9 Dual Core but it's actually 2.1GHz chip. Was the seller mistaken thinking it was dual when it isn't?

 = I would like to use LPARs once I get the 8GB RAM upgrade I ordered (got that a t a bargain price too). My 9111-285 claims to allow them to be utlilized (in the CoD Capability Settings) but further from that and knowing I need VIO on a DVD I do not know what I need to get a working IVM setup. I have a set of AIX 7L 7.1 DVDs inbound - would VIO be among those? The machine came with AIX 5L 5.3 on the first hard drive (which I have kept safe) - is it possible it is in there?

= I have a 73H3562 PCI SCSI Card here. I'd like an external 68-pin SCSI port for a DLT tape drive I have - would that suffice on such a new machine?

[Michael]

The procossors are named procX, with X being even numbers these days, and CPUX are the logical CPU, so sounds like single processor, dual thread.
The term XXX-core is misleading as core means different things to manufactures.

Depending on how you want to call it, it is dual core or not.

[MDBenson]

I was under the impression the nomenclature breaks down into 3. A 'way' is an isolated physical unit/socket containing 1 or more 'cores'. A 'core' was the physical processing unit on a die (wether in an integrated die like a Core i7 or on separate dies like a POWER5+). A 'thread' is a single logical operation path within a core. I'm fairly sure IBM cover it like that in the documentation. That would make this example, as you said, single core, dual thread.

Still a 2.1GHz 2-thread POWER5+ is still a pretty interesting and capable animal, especially packing that 36MB L3 cache

[Michael]

I am not a Hardware Specialist, and the term core "confuses" me. The sales people know all the terms. As I understand it, regarding Power7, The Power7 chip (physical packaging) has two something (cores?) that each has 8 processors (what AIX calls procXX) and each of these processors has 4-way SMT - that AIX sees as a "logical" cpu.

My main "difficulity" is comparing statistics between Power5 and Power6 "cpu" stats, and Power7 cpu stats, because the efficiency of the new processor makes it "impossible" for a single thread to utilize the potential 100%. To reach 100% efficiency you need at least two threads active. Lastly, the new algorithm makes the CPU stats reported by vmstat, topas, sar, iostat, etc more in line with the way other hardware processors are reporting their stats. I hope to have this worked into a simple demo someday, but need a system to play on before I can do enough testing to get that done clearly.

In short, the term "core" confuses me. Ask someone from sales how IBM relates it's processors to, for example, Intel processors and the definition/meaning of core.