There it is - the hidden cost of AWS. For bare-metal the risk of hardware failure is so low that it's faster to just handle the interruption when it happens (e.

There it is - the hidden cost of AWS. For bare-metal the risk of hardware failure is so low that it's faster to just handle the interruption when it happens (e.g. just restart the process) than to implement interruption tolerance. The hardware fails only once in many years. The chances of that happening during the 24 hours we train a model are almost zero. On a spot instances, the risk of the same are almost 100%, requiring investment up-front. For the price of a spot instance we can get an always-on bare-metal server without having to worry for how long it will remain available.