🚀 go-pugleaf

In message <4g2d0n$7pm@usc.edu> - dywilson@scf.usc.edu (Donald Wilson) writes:

 Donald,

 The short story, go for the extra memory.

 The long story.

 Using an adaptec 2940w or 2940UW, using our product IWSS I can bench a 
Seagate barracuda ST32550W out at between 6.9->7.2 MB when reading from 
cylynder zero for approx 80MB of data. Now if your drive is delivering the 
5MB of data per second then the speedup is marginal, it would be better to 
have more memory, in order to reduce paging altogether. The only place where 
this falls apart is, when I state that our product benches the drive at that 
transfer rate, it is from reading the data off of the platters, yes, 
prefetch is still in use, but as the entire track is being read in one I/O,
and the same track is never read twice, the drive is being forced to go back 
to the platters. Some disk benchmarks, are continuously hammering on the 
drives cache, which artificially inflates the numbers.  
 
  At this time SCSI-3 is not an adopted standard, yes it is being used
in marketing hype, but that is the only place. As to UltraWide drives, 
well first someone must find them. Note that on the Adaptec 2940UW, the ultra 
wide abilties are disabled in the controllers firmware by default, as there 
are so few drives out there right now that are ultrawide.


Jay Ice
Iceware Inc.