I wrote: > Apparently tar implements sparse files by simply detecting and > condensing large blocks of zeros in the input file, which means that > it has to actually read all 1.2TB of nothingness to do its job. > > It's been working for 52 minutes now on my 1.8GHz Athlon64 laptop. I > have no idea how much longer I will be waiting. Just for the record: 1h48m46s to generate a 10240 byte output file. Andy