root:~#time dd if=/dev/cdrom of=/dev/null bs=1200k count=1
1+0 records in
1+0 records out
elapsed 0%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+0minor)pagefaults 0swaps
: 12 megs in just over 100 seconds; seems about right.
just compared it... as you see, I get 21.5 kB/sec (mind my bs=1.2 MB!).
Something seems to be majorly wrong.
Whereas a cp improves in performance when making the system busier by other
processes (see my other post), dd does not:
20.1 kB/sec for one gzip -9 running,
14.5 kB/sec for two gzip -9 running.