25 Oct
1999
25 Oct
'99
1:35 a.m.
On or about
07:56 PM 10/24/99 -0700, Mike Cheponis was caught in a dark
alley speaking these words:
You crack on others for stating things without backing up with actual
data... where's yours? My wife's box is a Pentium 100 running SCSI3Wide and
I did benchmarks (real-world... but don't have them handy) which showed
that box stomped a Pentium 166 / IDE. (Mind you, saying the IDE bus is
rather an oxymoron, as it's an extension of the ISA bus IIRC... :-)
The difference? The IDE bus is totally stupid
(read: CPU controlled)
whereas the SCSI bus is very smart (read: 80Mhz RISC CPU controlled) - the
SCSI controller is offloading most of the CPU overhead.
IDE is a particularly insidious bus. The electrical specs are not well-
defined, and there are a panoply of "modes" PIO Modes 1,2,3,4, UDMA Mode 1
and Mode 2, etc.
AFAIK, UDMA Mode 2 is actually as fast as UW SCSI II for a single disk drive;
of course, people use SCSI for multi-spindle applications as well as high
throughput.
But their machines are obsolete, and that's why
we're discussing them here.
Obsolete is in the mind of the MIS director, not the techies.