Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 3 Nov 2008 01:04:52 +0100
From:      Nikola =?UTF-8?B?TGXEjWnEhw==?= <nikola.lecic@anthesphoria.net>
To:        Ivan Voras <ivoras@FreeBSD.org>, Jeremy Chadwick <koitsu@FreeBSD.org>, Christoph Kukulies <kuku@kukulies.org>
Cc:        FreeBSD-questions@FreeBSD.org
Subject:   Re: fastest raw device copy?
Message-ID:  <20081103010452.6a1f0521@anthesphoria.net>
In-Reply-To: <gef0dq$l8a$1@ger.gmane.org>
References:  <490AC650.3000904@kukulies.org> <20081031110159.GA30244@icarus.home.lan> <gef0dq$l8a$1@ger.gmane.org>

next in thread | previous in thread | raw e-mail | index | archive | help
-----BEGIN PGP SIGNED MESSAGE-----
Hash: RIPEMD160

On Fri, 31 Oct 2008 14:16:38 +0100
Ivan Voras <ivoras@freebsd.org> wrote:
=20
> Jeremy Chadwick wrote:
> > On Fri, Oct 31, 2008 at 09:48:16AM +0100, Christoph Kukulies wrote:
>=20
> >> What would be the fastest way to do that sector by sector copy?
> >> I'm using dd right now,
> >>
> >> dd if=3D/dev/ad0 of=3D/dev/da0 bs=3D10000000
>=20
> > On the flip side, your blocksize (bs) there is quite high for no
> > good reason.  I'd pick something more like bs=3D64k or bs=3D128k.  The
> > default (512) is too small for what you want, but 10MBytes is silly.
>=20
> 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:
>=20
> dd if=3D/dev/ad0 of=3D/dev/da0 bs=3D1m

Would there be anything wrong in

  cat /dev/ad0 > /dev/da0

?

- --=20
Nikola Le=C4=8Di=C4=87 =3D =D0=9D=D0=B8=D0=BA=D0=BE=D0=BB=D0=B0 =D0=9B=D0=
=B5=D1=87=D0=B8=D1=9B
fingerprint : FEF3 66AF C90E EDC3 D878  7CDC 956D F4AB A377 1C9B
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.9 (FreeBSD)

iJwEAQEDAAYFAkkOQCsACgkQ/MM/0rYIoZjjHQQAhXi6gu5JhJjzZmE97buiZ15u
Q6AT+qvAja6cALfGAGVrzJEzljfcbe3PnBdOnn1CTYbS62EHaVWLnvOKRGrpvzFE
q/WxQ9qCRfcsSx3o6eKxfTM6d4b92ZP+d1iPotmzutQl8TbxlJxNTP9i2b6cDw6a
au6zdoApH5A6UxyaJA8=3D
=3DoFoQ
-----END PGP SIGNATURE-----



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20081103010452.6a1f0521>