is there any simple bash command to show current disk read/write usage without installing anything on the machine ?
please note it's not to test the hdd read/write speed, it's to know the current data size being written/read into the hdd
Honestly, you really want to install
Or if you want to know about the number of bytes read and written you can do this. We perform the multiplication because the values given are in sectors, which are 512 bytes.
For all the fields you can check out the documentation in iostats.txt. Keep in mind that you'll have to add 3 to each of the fields to account for the text processing offset due to device major/minor/name in the output.