Source : Free On-Line Dictionary of Computing

cycle crunch
     
         A situation wherein the number of people trying to
        use a computer simultaneously has reached the point where no
        one can get enough {cycles} because they are spread too thin
        and the system has probably begun to {thrash}.
     
        This scenario is an inevitable result of Parkinson's Law
        applied to {time-sharing}.  Usually the only solution is to
        buy more computer.  Happily, this has rapidly become easier
        since the mid-1980s, so much so that the very term "cycle
        crunch" now has a faintly archaic flavour; most hackers now
        use {workstations} or {personal computers} as opposed to
        traditional {time-sharing} systems.
     
        [{Jargon File}]
     
        (1994-11-29)