fastest raw device copy?
kuku at kukulies.org
Fri Oct 31 07:37:46 PDT 2008
Ivan Voras schrieb:
> Jeremy Chadwick wrote:
>> On Fri, Oct 31, 2008 at 09:48:16AM +0100, Christoph Kukulies wrote:
>>> What would be the fastest way to do that sector by sector copy? I'm
>>> using dd right now,
>>> dd if=/dev/ad0 of=/dev/da0 bs=10000000
>> On the flip side, your blocksize (bs) there is quite high for no good
>> reason. I'd pick something more like bs=64k or bs=128k. The default
>> (512) is too small for what you want, but 10MBytes is silly.
> Not only that, but "10000000" isn't even correct - it needs to be a
> multiple of sector size. Generally, using suffixes will do the right thing:
> dd if=/dev/ad0 of=/dev/da0 bs=1m
OK, I understand that 10000000 isn't good, I just thought it wouldn't
harm. But if it is a transfer rate killer then I'd better think of
typing ^C now. The command is running for 6 hours now.
An idea how I can check the current amount of transfered byed alongside
the running dd command? Or watch the current i/o rate?
More information about the freebsd-questions