> >
>
> > > Synopsis:  Slaving the Cdrom should be OK.
> > >
> >
> > That makes sense as I recall civileme describing a quite
> elaborate soft RAID
> > setup on a board with only 2 IDE channels.
> >
> > But am I remembering correctly that having a slower device (my CDROM is
> > ATA33 while the disk is at least ATA100) on the same channel
> mandates that
> > both drives operate at the lower transfer rate? SCSI, at least
> once upon a
> > time,worked like this. Has this been an issue for you (balancing the
> > increased speed of the raid against the slower disk speed)? Or
> this just the
> > case when both devices are being accessed at the same time?
>
> I am fairly certain that caveats you refer to for SCSI don't apply to
> IDE.  For one thing, I've never noticed a slowdown myself with
> dissimilar devices on the IDE bus.  For another, devices are recognized
> individually (type and speed) when the system boots up.  In addition, if
> there was a problem, then anybody with an ATA100 drive would be wasting
> their money if they bought a CDROM and put it on the same bus.  I
> believe that one of the positive things about IDE (besides being cheap)
> is that the devices are dealt with pretty much on an individual basis.
>

Cool. So worse case, the 372 _isn't_ supported but I can use my second
controller to stripe the RAID. Maybe 9.0 will solve the problem and in the
meantime...

> The problem comes in when you have a raid array in which one of the
> devices is a slave.  When that happens, the master device must oversee
> data transactions (during stripe operations) not only for itself, but
> also for it's slave.  This makes the concept of dividing the work
> between two peripheral devices impotent.  When you *do* have only master
> devices in the array, it equates to a (x * 100)% performance increase
> (if it's Raid 0) where x is the total number of devices.  Because the
> work that was done by one is now done by several.
>
> The Highpoint and generic IDE buses can be maxed out throughputwise, but
> not, I think, by only one master device per channel.
>
>
> >
> > Right and I'm only bothering with this because I need this box
> to be as fast
> > i/o wise as it can be and the hardware budget has already been
> spent for the
> > year...
>
> I know where you're coming from..been there and got the t-shirt
> and sweatband.  You are headed in the right direction.
>
> The cool thing is that your generic IDE channels can be freed up for
> experimenting with other peripherals; and you won't ever have to muck
> around with the channels your primary devices are on.
>
>
> > This is what I figured I ought to be doing--leaving the RAID disabled in
> > BIOS--but, as I indicated, DiskDrake does not see the Highpoint
> controller's
> > IDE channels at all. Do you know if  there a secret handshake I
> have to give
> > DiskDrake to get it to see the controller?
>
> This is worrisome.  I can't offer advice on the 372, since I don't have
> one; but I'm surprised that Diskdrake is croaking.  Have you tried an
> install with the drives already partitioned, and highpoint raid
> deactivated?
>

My other disk is partitioned so I'll check that tonight.

cheers,
::mark


Want to buy your Pack or Services from MandrakeSoft? 
Go to http://www.mandrakestore.com

Reply via email to