USB2 DVD writer - crazy high cpu usage...

[brap]

As far as I can tell this hasn't been covered already, but if it has, I can't find it!

My external DVD writer, a Pioneer 107 on the USB2 bus, has issues. When writing, and when verifying, CPU usage hits 90%+, rendering everything else painfully slow; it's confusing since it seems determined to suck up every last bit of time - regardless of how else processing is distributed, the burn process grabs the remainder. This isn't solely limited to Toast (6.0.9), I find the same problems with Disk Utility.

Is this a common 'feature' when using the USB2 bus for high-volume, sustained transfers? As far as I remember it was fine with an IDE hard disc. For reference, this is on a revision c. 12" Powerbook.

[MisterMe]

Originally Posted by brap

As far as I can tell this hasn't been covered already, but if it has, I can't find it!

My external DVD writer, a Pioneer 107 on the USB2 bus, has issues. When writing, and when verifying, CPU usage hits 90%+, rendering everything else painfully slow; it's confusing since it seems determined to suck up every last bit of time - regardless of how else processing is distributed, the burn process grabs the remainder. This isn't solely limited to Toast (6.0.9), I find the same problems with Disk Utility.

Is this a common 'feature' when using the USB2 bus for high-volume, sustained transfers? As far as I remember it was fine with an IDE hard disc. For reference, this is on a revision c. 12" Powerbook.

This is hardly surprising. USB passes everything through the CPU.

[Jigglelicious]

USB and USB 2.0 are highly CPU intensive. Try Firewire instead if you want to go the external route.

[brap]

Originally Posted by Jigglelicious

USB and USB 2.0 are highly CPU intensive. Try Firewire instead if you want to go the external route.

Too expensive, late, yada yada. That, and I already have a Lacie D2 Extreme on my single, lonely FW400 port. I'm not spending any more money on a FW hub and enclosure, that'd be silly.

A little update, the CPU usage issue seemed to be markedly less when using Disk utility... in contrast to the last time i tried. How confusing.

I'll probably have to dump Toast if I can find a suitable alternative

[CanadaRAM]

Originally Posted by brap

Too expensive, late, yada yada. That, and I already have a Lacie D2 Extreme on my single, lonely FW400 port. I'm not spending any more money on a FW hub and enclosure, that'd be silly.

Umm... Firewire is daisy-chainable, hub not necessary.
In certain circumstances such as digital audio interfaces, it is best to have your FW drive and FW audio interface on different busses (not just different ports or a hub) but that is a specialized case.

[brap]

Originally Posted by CanadaRAM

Umm... Firewire is daisy-chainable, hub not necessary.

True - but say I'm burning something from my D2, bandwidth would be halved... perhaps closer to quartered?

Eitherway, handling I/O for both devices along a chain (or hub) can't be too efficient. Bear in mind that the drive is being limited by the full bandwidth of FW400 as it is, without the extra DVD drive attached. So your audio example is, actually, quite relevant.

...not to mention the fact the D2 only has one 400 port. Yeah, I could get a converter, but again... I've spent far too much on gadgets this month as it is!! I'd much rather have a functional D2->FW400->Powerbook->USB2->107D connection, thus using the theoretical bandwidth sensibly. Hopefully possible as soon as Toast either gets an update, or I find some freeware to do the job

Anyway, back on track; so nobody has ever come across Toast 6 throwing a paddy when using USB2?