

Things you should know about USB 2.0 and 3.0 - soundsop
http://blogs.techrepublic.com.com/10things/?p=1265

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teilo
And I still do not have an answer to my #1 USB 3 question: Have they solved
the CPU utilization and data pipelining / overhead issues?

The biggest advantage of Firewire over USB has been the controller which
alleviates CPU usage on the host machine, and allows for pipelining of data
that makes the protocol more efficient than a given USB connection with the
same base data rate.

I equip all my Windows machines with Firewire ports for this reason, and use
external firewire hard drives for extra storage and for backup. I also have a
significant investment in Firewire camera gear, because USB just doesn't cut
it for streaming live HD video. However, I would love to abandon Firewire in
favor of an optimized USB, if for no other reason that USB has wide industry
support, and Firewire seems to be fading away due to its licensing issues.

~~~
windsurfer
No. There is no direct memory access (DMA) in the USB 3.0 spec. It would be a
security nightmare.

~~~
bdonlan
I'm sure DMA happens between the controller and host - there's no way they
could achieve those speeds with PIO. And DMA has nothing to do with pipelining
- the controller could easily be programmed with a list of buffers in which to
place USB responses.

