There may be times when you need to modify the priority of a command prior to starting it. You can do this by using the nice command. It modifies the scheduling priority of the command . 19 is the lowest priority, 1 is the highest priority, and 10 is the default. Here are a few examples.
Highest priority
# nice -n 1 myfind &
returns PID
Lowest priority
# nice -n 19 myfind &
returns PID
Default priority is 10
Also, the renice command can be used to change the priority of a job.
# renice -18 PID
stephane added the priorities range from -20 (or -19 depending on the Unix) to 19, -20/-19 being the most favorable scheduling, 19 the least favorable one. The negative increments are allowed only for root.
So if you are root, you can do this : nice -19 myfind
to get it running with max priority.