[Beowulf] Bolts of Thunder and Upgraded desktop interconnect silicon....

Lux, Jim (337C) james.p.lux at jpl.nasa.gov
Mon Jun 10 22:16:29 PDT 2013

There's a fundamental problem with running data "really fast"... You need
decent transmission lines AND adaptive equalization to make it work. And
the equalization is non-trivial to implement in a robust way.  There's no
way to get the signal off the chip, onto the board, through a connector
and into the wire without some impedance discontinuity.  I'm sure that
thunderbolt shares a lot of commonality at the Physical level with 10Gig
Ethernet: same basic problems, same rates, etc.  I think TB has 4 lanes (2
each direction) running at 5Gbps/lane (roughly)

Just like 10Gig E, TB was apparently optical, and then wound up being

So what does TB give you that 10GigE doesn't?  Maybe different framing?

On 6/10/13 8:57 PM, "Gerald Henriksen" <ghenriks at gmail.com> wrote:

>On Mon, 10 Jun 2013 18:57:29 -0400, you wrote:
>>So a company based out of Cupertino mentioned using this silicon in a
>>revamp of their MacPro line today...
>>we appear to have a second version of a 20GB/s consumer connection
>>(latency unknown), and yet this search:
>>does not really go anywhere cool like a github or kernel.org repo....
>>Any qualified folks know where this thunderbolt stuff is all heading
>>and are able to talk in public?
>Thunderbolt so far is a very niche product that almost everybody
>appears to be ignoring.
>The cables are expensive - starting in the $40 range for a 1 m cable.
>Actual devices are hard to come by, and tend towards the expensive -
>raid boxes, and a couple of docks in the $300 range.
>This might change later this year when the new Mac Pro is released as
>the closed box nature of it will force/encourage any expansion to be
>But for now it looks like another Firewire in terms of market
>Until Intel (with or without the help of Apple) can get the cable
>prices down and some more common affordable peripherals available -
>like a single drive enclosure - the market will likely continue to
>ignore Thunderbolt.
>Beowulf mailing list, Beowulf at beowulf.org sponsored by Penguin Computing
>To change your subscription (digest mode or unsubscribe) visit

More information about the Beowulf mailing list