$ dd if=/dev/random of=/tmp/f6 ibs=1m obs=1m
load: 0.08  cmd: dd 29483 [29483 4 0] 0.00u 0.00s 0% 1048k
0+29 records in
0+0 records out
0 bytes transferred in 3.501 secs (0 bytes/sec)
dd: /dev/random: Interrupted system call
0+29 records in
0+0 records out
0 bytes transferred in 3.502 secs (0 bytes/sec)