Actually, it’s mostly down to the computers now. Having downtime is advantageous to the primary customers of the stock market. If you have the same “off and on” times as your competitors you can ensure your operations are structured in such a way that you don’t have to deal with a whole class of systemic risks, no need to roll out up’s to FPGA powered acceleration devices live where the smallest mistakes can cost money for every second they are wrong let alone if they are broken … to more mundane things like being able to reprocess the data trading data and analyse performance vs other prediction models… effectively the downtime is for the high frequency traders and the algorithm traders and all the players paying for direct access to the stock market for their computer systems… it’s effective a digital cage match from bell ring to closing time and it’s in the best interests of all the competitors to only have to fight the same 8-12 hours in the cage, lest it becomes a much more expensive 24/7 war of attrition.
