[linux-audio-user] Re: OT: ide drives

[Robert Epprecht]

First of all, thanks a lot to you, David and anahata for your answers :-)


Mark Knecht <markknecht at gmail.com> writes:

>> > > /dev/hda     system hd
>> > > /dev/hdb     DVD burner
>> > > /dev/hdc     data hd
>> > > /dev/hdd     DVD reader
>> > >
>> > > Does this look OK? (Does it matter where i plug the drives at all?)
>> >
>> > I think this setup looks good. Give it a try.

I was very pleased by this simple answer, but...

>> Why does "everyone" set things up with HDs on one channel, CDs on the
>> other? I was told that the slower CD device will slow down the HD.

Yes this was one of my concerns (the other one being my impression, that
it might be better to have the two important drives on separate channels)
Could a slower optical drive slow down a faster hd even if it is not in use?
As Mark understood correctly i do *not* use the optical drives while doing
audio work.

> I think it depends on the system and the drives. It's a complicated subject.

That's what i feared ;-(

> In Robert's case he wants to use the two channels available to him. He
> knows he's going to use the two drives at the same time, so he's
> optimized for that usage.

Exactly! That's what i want.

> However, you are correct that if he was to mix an older CDRW/DVD drive
> that was (possibly) a UDMA1/2/3 drive, with his nice, new UDMA5/6/7/8
> hard drives, then the system might have to slow the EIDE cable down
> and his drive would go slower. He'd still be spinning at 10K RPM, but
> on the cable he's be going 33MHz instead of 100MHz, etc...
>
> It's a crap shoot answering questions like this without madel numbers
> for all the devices,

Oups, sorry...
dmesg says the old drive is a Samsung SP1604N  (hda:DMA UDMA(100))
my LG DVD-burner is a GSA-4040B  

Playing around with hdparm -I i get a lot of information (which i do
not really understand), but hd and burner both show the line
PIO: pio0 pio1 pio2 pio3 pio4
the burner reports *udma2  and the hd *udma5  (could this be a problem?)

The new drive is a Samsung SP1614N 7200rpm and the new DVD-ROM is a LG
GDR-8163B.

> and if he gave me model numbers I'd probbably run and hide
> as figuring it out is too much work. ;-)

Hmm, so maybe it would be less work to try both setups:

1) both hds as masters, optical drives as slaves.
2) hds on one channel, dvds on the other one.

The problem is that i do not really know how to test performance...

I understand from the discussion so far, that it's not trivial to
predict, if 1) or 2) will be better. Right?


Thanks a lot,
Robert Epprecht