🚀 go-pugleaf

In article <1992Aug11.035939.22924@leland.Stanford.EDU>  
m@crito.Stanford.EDU (M Carling) writes:
> In article <1992Aug10.220747.16164@nic.umass.edu>  
> a74k110@titan.ucc.umass.edu (Chris Lloyd) writes:
> > of the machine it runs on.  There have been more than enough posts to 
> > prove beyond a reasonable doubt that the NeXTs SCSI device driver  
simply
> > stinks speedwise.
> 
> I have yet to see anything definitive on this.  [deleted]

M -- the poster is quite correct, the NeXT computer seems incapable of  
megabit throughput on the SCSI bus.

My own tests using SCSI SpeedGun which access the "sg" SCSI generic driver  
directly gives some of the following numbers. Note that I am using the  
SCSI read command directly at the driver level, avoiding the caching  
problems noted by other posters. Throughput is in kilobits/sec. 


Fixed Hard Drives:
	CDC Wren VI		6781
	Fujitsu M2623S-512	7508 <<-- too low 
	HP97548S		2266 
	Wren VII		6425
	Maxtor XT8380S		3515
	Maxtor XT-8760		3505
	Quantum P40S		2666
	Quantum PD210S		6875
	----------------------------
	Class Average		5141

Removable Hard Drives:
	Syquest SQ555		982
	Syquest SQ5110		1680
	----------------------------
	Class Average		1331

Removable MO drives
	Sony SMOC501		1176

SCSI Floppy Drives:
	PLI Super Floppy:
	DD			67
	HD			101
	ED			134


Disk throughput was computed by reading 5000 blocks from block 0 with a 10  
block incremement on each read. Some devices had different number of  
blocks read due to device limitations (notably the SuperFloppy)


========= Ad Blurb ========
SCSI SpeedGun is one application in a suite of SCSI applications currently  
being developed by Focal Point Computer, Inc. It allows for very accurate  
sector-to-sector seek time evaluation and data throughput speeds. It also  
allows for testing the media integrity of a hard drive.

Other components of the SCSI suite include:
	SCSI Formatter: Full low and high level formatting and paritioning
		  with a NeXTSTEP GUI
	SCSI Inquirer II: SCSI bus device interrogation, supports SCSI-2
		  devices
	SCSI ReassignBlocks: SCSI bad block (low-level) reassignment
	SCSI SpeedGun: mentioned above
	SCSI Commander: Developer level application and object
		code requisite to developing and testing SCSI devices
		on the NeXT Computer System

This suite should be available 3Q1992, Industry Standard Time (i.e., add  
about four months to this) to OEMs and VARs.
=============================


	- Jiro Nakamura
	NeXT R&D / Focal Point Computer, Inc.

-- 
Jiro Nakamura				jiro@shaman.com (NeXTmail)
NeXTwatch / Technical Editor		76711,542 (CIS)
The Shaman Group			+1 607 277-1440 (Voice/Fax)