Busy waiting (or polling otherwise). A somniphobic program is afraid to give other programs on a time sharing system the option of running (usually due to unbased irrational fear that "other programs can see my private data while I am asleep(2)").
Symptoms of computer somniphobia including looping waiting for a file to be created (instead of signalling), calling select(2) with a zero timeout, and in general avoiding the use of the operating system because it is perceived (incorrectly!) as being"too slow".
Somnophobic computer programmers should be subjected to re-education; if that fails, shock treatment may be the only resort.
Somniphobic code sometimes ends up microsleeping or nanosleeping.