[rescue] J90 on epay

[Dave McGuire]

On Friday, February 28, 2003, at 03:06 PM, Kevin Loch wrote:
>>   Not in the J90.  The J90s SPARC5 connects to the IOS processors via
>> ethernet.
>
> What does IOS stand for?  Please don't say I/O because Sparc 5 would
> be a terrible choice for I/O.

   No...the SS5 in question handles diagnostics, booting, and shutdown.
This is a supercomputer, man.  It has more I/O capabilities than most
of us can imagine.

   IOS stands for Input/Output System.  The J90 IOS is based on a VME64
cardcage containing an IO}B interface (a high-speed channel directly to
a CPU), a VME SS5 (which does RAID, caching, and error handling) and
disk/network interfaces.  The VME SS5 sets up high-speed DMA
transactions into the Cray processors' memory, which run over the IOBB
bus.

        -Dave

--
Dave McGuire             "I've grown hair again, just
St. Petersburg, FL           for the occasion."       -Doc Shipley