Getting around G92 I/O bottleneck on RS/6000

From: bbesler()at()ouchem.chem.oakland.edu (Brent H. Besler)
Subject: Getting around G92 I/O bottleneck on RS/6000
Date: Wed, 21 Jul 93 09:58:55 -0400

 I am configuring an RS/6000 cluster for an application(Gaussian 92)
 which requires 2 Gigabyte scratch files(2 of them most of the  time
 meaning 4 Gigabytes total) to be read in and out multiple times.  I/O
 speed is the concern, data reliability not at all.  It seems that a
 level 0 RAID might solve the problem.  In some benchmarks which IBM did
 for us they used a Zitel "cached" disk.  I am not sure if this is a
 RAID
 or not?  Has anyone encountered this device before.  Also RAID's for the
 IBM RS/6000 are mostly SCSI-2 interface.  There is a company which
 produces RAID's for the RS/6000 called the MC Series which have a
 proprietary Microchannel bus controller which is faster than SCSI-2 they
 claim.  Has anyone ever used one before on an RS/6000?
  I believe the comany which
 manufactures them is Maximum Strategy Incorporated.  Also does anyone
 know of a way around the 2.1 Gigabyte filesize limit of AIX? Finally
 has anyone used Gaussian 92 with the scratch files going to NFS mounted
 disks over an FDDI network?