wall time n.
(also `wall clock time') 1. `Real world' time (what the clock
on the wall shows), as opposed to the system clock's idea of
time. 2. The real running time of a program, as opposed to the
number of ticks required to execute it
(on a timesharing system these always differ, as no one program
gets all the ticks, and on multiprocessor systems with good
thread support one may get more processor time than real
time).