Hi Arne and Eric,

# atacontrol mode 0
Master = BIOSPIO
Slave  = BIOSPIO

Hmm... 0 seems to be the wrong ata... Thats why the output does
not fit to SATA drives, I think...

oups... I'll have to do it again with channels 2 and 3


# dd if=/dev/ad4 of=/dev/null bs=1m count=1000
1000+0 records in
1000+0 records out
1048576000 bytes transferred in 17.647464 secs (59417943
bytes/sec)

That seems to be 2 or about 2 times faster than disc->disc
transfer... But still slower, than I would have expected...
SATA150 sounds like the drive can do 150MB/sec...

As Eric pointed out, you just can"t reach 150 MB/s with one disk, it's a technological maximum for the bus, but real world performance is well bellow this max.
In fact, I've though I would reach about 50 to 60 MB/s.

(Maybe you could find a way to copy /dev/zero to /dev/ad6
without destroying the previous work... :-))

well, not very easy both disk are the same size ;)

I thought of the first 1000 1MB blocks... :-)

damn, I misread this one... :)
I'm gonna try this asap.


Instead of dd, why not use gmirror?

I had no idea gmirror exists, but I'll continue with dd. It's a one time experiment.


Have you tried a smaller block size? What does 8k, 16k, or 512k do for you? There really isn't much room for improvement here on a single device.

nop, I'll try one of them, but I can't do many experiments, the box is in my living room, it's a 1U rack, and it's VERY VERY noisy. My girlfriend will kill me if it's running more than an hour a day :))


Pat
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