encontrei esta soluçao, alguem me explca em pt?
> The drive is on secondary master. The hard drive with the
> .iso is on secondary slave. All devices are running udma2.
Bam! That's your problem. You will run into a noticable
performance issue when you are doing DMA from one device to
another on the same channel. Especially from the
all-important latency aspect.
And that's assuming the ATA v. ATAPI devices and their
different vendor/model quirks aren't already in-fighting and
reseting the ATA bus (which is detrimental to performance).
Trust me on this, put each device on their own channel, and
you will avoid performance issues. You should _only_ use the
master/slave relationship for PIO (which is slow and CPU
intensive), and _never_ for DMA -- or in the worst case,
never for transfers occurring from both devices on the same
channel simultaneously.
ATA is not SCSI. It does _not_ do device-to-device
transfers. One ATA device must take control of the bus,
setup the registers for transfer, transfer to memory and give
up the bus -- while the other device then does the same. The
acquisition of the bus is the main issue -- especially when
data is trying to be fed to the recorder in real-time, while
the HD is trying to transfer into memory.
