UNIX file system used on Crays

[gfredin at enlog.Wichita.NCR.COM]

This is probably an ignorant question, but here it is:

I am not that familiar with Cray systems, but my understanding has 
always been that they transfer large amounts of data when an I/O 
request is made.  This seems to contradict my perception of UNIX 
using relatively small block sizes spread randomly across the disk.

Does UNIX on a Cray use a modified file system, raw I/O, or some other
method I am not familiar with?  If it uses a modified file system, 
what does an I/O access look like in terms of block size and 
randomness?

If you think the response to this is below most on the net, please 
email responses.

Thanks in advance!

Standard disclaimers apply.  
**********************************************************************
* Jerry Fredin                           NCR Corporation             *
* Sr. Consulting Analyst                 Peripheral Product Division *
* I/O Architecture                       3718 North Rock Road        *
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* uunet!ncrlnk!ncrwic!enlog!gfredin    Jerry.Fredin at Wichita.NCR.COM  *
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