From: quayle@switch.rockwell.com (Bill Quayle)
Newsgroups: comp.sys.sun.hardware
Subject: 690+FDDI+SCSI--How fast?
Keywords: Bus speed, NFS performance
Date: 20 Dec 92 03:14:35 GMT
Article-I.D.: nb.1992Dec20.031435.18208
Reply-To: quayle@switch.rockwell.com
Organization: Switching Systems Division - Rockwell International


We are currently kicking around several configurations for an optimized
build environment for a LARGE software project.  I have proposed the 
following:


     -----------          -----------           -----------
     |4/690MP  |  FDDI    |         |-----------| SS10/30 |
     |4-way    |----------| Alantec |           -----------
     |         |----------|  Power  |-----------| SS10/30 |
     |SCSI disk|          |   Hub   |           -----------
     |         |          |         |-----------| SS10/30 |
     |         |          |         |           -----------
     |         |          |         |-----------| SS10/30 |
     |         |          |         |           -----------
     |         |          |         |-----------| SS10/30 |
     |         |          |         |           -----------
     |         |          |         |-----------| SS10/30 |
     -----------          -----------           -----------

The above configuration is based on the following rationale:  
	- All equipment is available NOW.
	- We have a 4/490 for the 4/690 upgrade.
	- The 4/690 is upgradeable by adding cpu's, disks, additional FDDI
		interfaces and eventually, to an SC2000.  An Auspex does not
	  provide this upgrade path. (We were considering Auspex).
	- The 690 provides NFS service to the SS10 compile engines.  The SS10's
		are configured with local disk for root, usr, and swap.
	- Each SS10 has a dedicated 10Mb/S 10BaseT line to the Alantec
		hub.  The hub then has a dedicated FDDI channel to the 4/690.
	  Future growth would be via a second hub and FDDI interface to additional
	  SS10's.
	- The SS10/30's could be upgraded to SS10/54's or more SS10's could
		be added.

Questions I have are:

	1.)  Has anyone ever tried anything like this?  If so, what bottlenecks
			 did you encounter?

	2.)  Does anyone see any inherit problems with the above configuration?

	3.)  How many SS10/30's can run full-blown compiles against NFS-mounted
			 filesystems before the 4/690 is at its knees?

	4.)  I guess what (3.) is all about is this:  If the SCSI disk on the 690
	     is accessed through the relatively slow VME bus, and we spread the
	     filesystem over 4 interfaces (via disksuite), and the FDDI interface
	     is also on the VME bus, (whew!) and we build on 6 SS10's against
	     these NFS-mounted filesystems, isn't the speed of the VME bus going
	     to be the limiting factor?  And then there's MBUS and SBUS...I need
	     some help here, what's connected to what?

Any and all serious comments or suggestions are welcome.  Thanks for your time.

-Bill

----------------------------------------------------------------------------
William R. Quayle                     |          UNIX Systems Administration
Rockwell International                |           Switching Systems Division
1431 Opus Place MS-933-651            |  Internet: quayle@switch.rockwell.com
Downers Grove, IL 60515-1166          |                 VOICE (708) 960-8623
                                      |                 FAX   (708) 960-9771
----------------------------------------------------------------------------
Newsgroups: nrl.misc,comp.sys.sun.hardware