Ask Different is a question and answer site for power users of Apple hardware and software. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

The Activity Monitor allows users of Lion to inspect the CPU usage, used memory and some other things for each running process. Unfortunately it doesn't show the drive (IO) activity like e.g. the Process Monitor does for Windows.

Is there any tool for OS X that does the job?

share|improve this question
up vote 2 down vote accepted

How about this answer on another SE site?

From man iotop:

iotop tracks disk I/O by process, and prints a summary report that is refreshed every interval.

This is measuring disk events that have made it past system caches.

Since this uses DTrace, only the root user or users with the dtrace_kernel privilege can run this command.

This may not be precisely what you want - but it's a ksh script which wraps around dtrace, so you should be able to figure out how to make dtrace do what you need, if iotop doesn't handle it by default.

However, something like iotop -C 5 12 should give you something to start with: it will output 12 samples, each 5 seconds long.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.