$ time sudo ddrescue -f /dev/sda back.img log
GNU ddrescue 1.23
Press Ctrl-C to interrupt
     ipos:   16088 MB, non-trimmed:        0 B,  current rate:   3473 kB/s
     opos:   16088 MB, non-scraped:        0 B,  average rate:  19290 kB/s
non-tried:        0 B,  bad-sector:        0 B,    error rate:       0 B/s
  rescued:   16088 MB,   bad areas:        0,        run time:     13m 53s
pct rescued:  100.00%, read errors:        0,  remaining time:         n/a
                              time since last successful read:         n/a
Finished

real    13m56.238s
user    0m5.163s
sys     2m31.496s