Date: Fri, 31 Oct 2008 14:16:38 +0100 From: Ivan Voras <ivoras@freebsd.org> To: freebsd-questions@freebsd.org Subject: Re: fastest raw device copy? Message-ID: <gef0dq$l8a$1@ger.gmane.org> In-Reply-To: <20081031110159.GA30244@icarus.home.lan> References: <490AC650.3000904@kukulies.org> <20081031110159.GA30244@icarus.home.lan>
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[-- Attachment #1 --] 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 [-- Attachment #2 --] -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFJCwU2ldnAQVacBcgRAt9RAKDQI13rdhkjPwJ2qgcFDy7oWFvIjQCgyhWc J2+LuU157FnLhikw2rmmZBE= =rb04 -----END PGP SIGNATURE-----home | help
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