In absense of iotop which command is most appropriate for get i/o bounded process
Duplicated of: Linux - How can I see what's waiting for disk IO see that URL for a simple solution.
And you can enable disk I/O logging putting 1 into /proc/sys/vm/block_dump. then tail -f /var/log/syslog will give you reads and writes (process, pid, operation, blocks and device). Do not forget to return /proc/sys/vm/block_dump to zero when you're done.
You can check the IO usage of any process by looking at the /proc/[pid]/io file. Example:
$ cat /proc/1775/io
read_bytes: 4366336
write_bytes: 45056
cancelled_write_bytes: 229376