Re: 2 IDE - 1 CD: which interfaces

[moseley@hank.org]

On Sun, May 25, 2003 at 09:13:50AM +0100, Alan Chandler wrote:

> The answer depends on what you are using the disks for.
> 
> Fundementally, for a given IDE channel, the two devices cannot be doing IO at 
> the same time.  Because inherently the CD device is slower than a disk (even 
> if it can do dma) you are often advised not to put the two together.  
> However, if you hardly use the CD and could benefit from overlaping 
> operations between two hard drives (say one on hda and one on hdc) then go 
> ahead and do it.

That's what I was wondering -- if just connecting the CD-ROM would effect 
the speed, or if it was only while the drive was operating.  Didn't seem 
like just connecting the CD would slow down the entire interface.

So in my case where the CD is used, well, for just installing Debian and 
where I have my partitions on separate drives, it's better to place them as 
two masters and make the CD slave.

But if I'm, for example, ripping or burning CDs often then probably better 
to separate them.  (in that case probably better to go with a SCSI cd-r...)

> that debian package sysstat contains iostat - which helps you see whats going 
> on.

Thanks, that package has been on the back of my mind to install for months, 
if not longer.

-- 
Bill Moseley
moseley@hank.org