Erlang was reported to have been used in production systems for over 20 years with an uptime percentage of 99.9999999%. I did the math as the following: 20*365.25*24*60*60*(1 - 0.999999999) == 0.631 s That means the system only has less than one second of downtime during the period of 20 years. I am not trying to challenge the validity of this, I am just curious about how we can shut down a system
