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Date: Thu, 30 May 1996 17:02:46 -0400
From: "Sexton, Robert" <sextonr.crestvie@squared.com>
Organization: Square D
To: freebsd-hackers@freefall.FreeBSD.org
Subject: Disktab and SCSI Performance.
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Greetings,
	Do the disk parameters in disktab have any meaning?  It seems that when 
we do the mapping from the drive's own private geometry to the scsi block 
number, we lose the connection with the drives' own performance 
characteristics.  I am specifically wondering about the selection of 
drive speed, and to what degree the filesystem can use this information.  
The drive may very well be re-ordering reads and writes, and there is no 
guarantee that disk block 2001 will be easily reachable after 1998.  How 
many outstanding disk requests are permitted?  
	Thanks,
	Robert Sexton.