On 2020-09-09 21:21, Carlos E. R. wrote:
I don't think it was slow read, but that ddrescue can not do read and write simultaneously, as dd does.
GNU dd does not read/write simultaneously either. That would require threading or multi-processing. E.g. rsync does. I can't tell for ddrescue, but for dd(1) it makes a huge difference if you use the default block size (4k) or a custom one like e.g. bs=32M. Larger block sizes make the (good) reads/writes faster. The problem comes when there's a read error. AFAIR this is ddrescue's domain, because it re-tries with smaller block to find the physical bad block(s) ... which it will set to NULs when writing the output. Have a nice day, Berny -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org