[Beowulf] Intel buys QLogic InfiniBand business

[Mark Hahn]

>>>> http://seekingalpha.com/article/303061-qlogic-s-ceo-discusses-
>>>> f2q12-results-earnings-call-transcript)
>
> I found that statement interesting.   I've actually not known anything
> about their 10GbE products.  My bad.

I was a bit surprised that the entire transcript had only one 
side-ways mention of IB.  also interesting that they seem quite 
heavily into the heavily-offloaded adapter market (which is sort
of the opposite of the original infinipath stuff.)

>>> I would guess that we will see message passing/RDMA over
>>> Thunderbolt or similar.

has there been any mention of Thunderbolt in a switched context?
afaikt it's just a weird "let's do faster USB and throw in video" thing.

> Intel buying makes quite a bit of sense IMO.  They are in 10GbE silicon
> and NICs, and being in IB silicon and HCAs gives them not only a hedge
> (10GbE while growing rapidly, is not the only high performance network

weird to have redundant/competing parts in many of the same markets though.
afaik, intel 10G has a reasonable rep; they presumably won't be junking
their own products.

> ...).  Its quite likely that Intel would need IB for its PetaScale
> plans.

I can't quite tell whether Qlogic's IB switches use Mellanox chips or not.
afaik, Qlogic has their own adapter chips (and perhaps FC/eth).

> than 30%) better than QDR?  I've been hearing numbers like 0.8-0.9 us
> for a while, and switches are still ~150-300ns port to port.  At some

mellanox qdr systems I've tested are about 1.6 us half-rtt pingpong.
I don't think the switch latency is a big deal, since with 36x fanout,
you don't need a very tall fat-tree.

> Curiously, I think this suggests that ScaleMP could be in play on the
> software side

really?  I'd be interested in hearing from real people who've actually
used it (not marketing, thanks).  I don't really understand how ScaleMP
can do the required coherency in units smaller than a page, which means
that "non-embarassing" programs will surely notice...