Hi
It is not unusual for Inaport to grab every CPU cycle it can when running. Depending on your job, there may be quite a bit of data to move around.
That said, there may be some optimizations you can perform. In particular, you might want to have a look at SQL matching instead of standard matching. Have a look at the tutorials on the main web site.
You might also want to make sure you are on a current build. There has been a lot of work over the last year in performance enhancement.
Regards
Admin