some software you were running called a Halt system routine, not supported at the place it was called. That is likely caused by aftermarket software ported to the Mac, such as Virus Scanner software. As the world has seen today, especially the thousands of people piled up in airpots, this type of software can be VERY effective! You can't get ANY viruses at all when your computer is crashed!
By far the easiest way to cause poor performance, instability, overheating and crashing is to install ANY third-party speeder-uppers, Cleaners, Optimizers, or Virus scanners, Bit Torrent, or a VPN that you installed yourself. The main reason is that they are relentless in scanning your files, non-stop, looking for virus-like patterns in Everything, or looking for files that have changed. When completed, they do it all again.
are you running anything like that?