Re: [Bug-ddrescue] Request for an Especific Clone Direction Option

[Scott Dwyer]

On 5/19/2014 11:42 AM, Antonio Diaz Diaz wrote:
> Even if all passes are made in the same direction, ddrescue will go 
> twice per pass over any area (unwanted or not) that is between rescue 
> domain extremes, because it must go back to the beginning to start the 
> next pass.
>
> There is a way to make ddrescue perform the copy phase in just one 
> pass, and therefore in one direction; disable skipping with 
> '--skip-size=0' 
I don't know why I didn't think to post this earlier. To get a truly 
linear one pass copy using ddrescue 1.18.1, use the new '--skip-size=0' 
along with '--cluster-size=1'. It should read one sector at a time in 
the forward direction until it is finished. Since it is reading one 
sector at a time, there should be no trimming or splitting phase, and no 
sector will be tried twice (can actually speed up the total recovery 
time if there are a lot of small errors). Downsides are the good areas 
will read considerably slower due to the small read size, and you don't 
get the benefit of getting the most good data first since it is just 
reading linear.

Scott