Firewire Daisy Chain

Does having devices (all firewire 400) in a daisy chain degrade performance.

Jay

JayOxO <> wrote:
> Does having devices (all firewire 400) in a daisy chain degrade performance.

Not in my experience. I have two FW400 drives daisy chained right now
and do not notice any difference when they are both hooked to the Mac's
own FW ports.

--
K.

Lang may your lum reek.

Király wrote:

> JayOxO <> wrote:
>
>>Does having devices (all firewire 400) in a daisy chain degrade performance.
>
>
> Not in my experience. I have two FW400 drives daisy chained right now
> and do not notice any difference when they are both hooked to the Mac's
> own FW ports.

Try turning the power off on the one in the middle of the chain
and see if the other one continues to "perform" as well :-)

Some firewire ports will drag the bus down or not pass data
through if you shut them off. I have two OWC Mercury external
drives which I like very much but they do this. If they are daisy
chained and the one in the middle is turned off, the one on the
end dies. I use one for bulk storage and the other for backups.
usually they are both turned off but 95% of the time when I need
one, I only need ONE, and if they are not both connected directly
to my iMac G5, I have to always turn both on at the same time.


--
Jeff Wiseman
to reply, just remove ALLTHESPAM

Jeff Wiseman <> wrote:
> Try turning the power off on the one in the middle of the chain
> and see if the other one continues to "perform" as well :-)

I just tested it - no difference. 2 minutes and 10 seconds to copy a 4.7
GB file to the outbound firewire drive, regardless of whether the drive
in the middle of the chain was on and mounted, or powered off. These are
LaCie d2 drives connected on the FW400 bus.

Not all FW devices are created equal, though. Your drives are a case in
point. I have a Canon camcorder that will not work with my Mac unless
all other FW devices are disconnected!

--
K.

Lang may your lum reek.

Király at wrote:

I just tested it - no difference. 2 minutes and 10 seconds to copy a 4.7
GB file to the outbound firewire drive, regardless of whether the drive
in the middle of the chain was on and mounted, or powered off. These are
LaCie d2 drives connected on the FW400 bus.

Not all FW devices are created equal, though. Your drives are a case in
point. I have a Canon camcorder that will not work with my Mac unless
all other FW devices are disconnected!

--
K.

I will be using all LaCie D2 drives, so that's good news. At the moment I
have a daisy chain of DVD burner, D2 HD and Canon camcorder (works OK), soon
to be joined by a 500GB HD. Having two HDs in the chain was the reason for
my question.

John

On 2007-11-03 03:17:26 +0200, JayOxO <> said:

> Does having devices (all firewire 400) in a daisy chain degrade performance.
>
> Jay

As far as I know, Firewire 400/800 is more like SCSI which doesn't
degrade performance. In fact many professional external firewire disks
have "passthrough" firewire connectors to make them easy to set as RAID.

It is not like USB in that sense.

Ilgaz