dd blocksize when copying to SSD disk

Mike Clarke jmc-freebsd2 at milibyte.co.uk
Wed Aug 31 19:46:33 UTC 2016

On Wednesday 31 Aug 2016 14:49:25 Kevin P. Neal wrote:
> On Wed, Aug 31, 2016 at 06:35:28PM +0200, Christoph P.U. Kukulies wrote:
> > I'm about to copy an existing Windows 7 system to an SSD. Source drive 
> > is a hard disk of 256 GB, destination drive a 500 GB Samsung SSD 850 EVO.
> >
> > 
> >
> > Given the fact that unnecessary write operations to SSDs should be 
> > avoided I'm thinking about the best strategy to use dd to write to the
> > SSD.
> I'm not sure that dd is the best strategy. Using Windows to do the copy
> may be better.

But the Windows copy command isn't very good at copying the entire system, it 
will fail to copy open files and certain "special" system files. On the other 
hand dd will copy everything in the partition but at the expense of wasting 
space by copying all the unused blocks.

An alternative would be to use Driveimage XML
<www.runtime.org/driveimage-xml.htm> from within Windows to create a 
compressed backup of all used blocks in the system. It's also available on a 
Knopixx live CD <www.runtime.org/data-recovery-live-cd> which, I think, runs 
it under wine so it could probably be run under wine on FreeBSD to create or 
restore a backup of an entire Windows partition.

Mike Clarke

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