I would rather my whole system shut down and be unusable while I investigate vs. auto-scale and charge me a bill I can't cover.
However, searching around it seems like I can only get alerts when a $$$ threshold is passed, but AWS won't take any action to stop computing or anything. Please prove me wrong.
The counterargument is that you get a usage spike (which is often a good thing for a company), and AWS shuts down everything connected to your AWS account without warning.
I'm not necessarily sure that optional/non-default hard circuit breakers would be a bad thing. But it certainly appears not to be a heavily demanded customer feature and, honestly, if it's not the default--which is shouldn't be--I wonder how many customers, or at least customers the cloud providers really care about, would use them.
Nearly every customer (i.e. all of them with a budget) would make use of circuit breakers and it would make Amazon absolutely $0 while costing them untold amounts. Are you really surprised Amazon hasn’t implemented them?
For example Vultr can give you a "bare metal" 8vcpu-32GB box for $120 a month (Not sure if this is contract or on-demand) vs amazons M5.2xlarge for $205 reserved. $80 might not sound like much, but that's 70% more. Who would love to save ~42% on their cloud costs?
It become harmful to them though. At a certain point people feel the hit and avoid the service. Having people spent a little more accidentally and go ‘oh well, oops’ is the sweet spot. An unexpected $80k which kills the company is bad for everyone.
The same could be done with cloud doo-dads.
Sadly, some services take as long as 24 hours to report billing.
Sure, but most large companies (the kind which AWS gets a lot more revenue from and cares about a lot more) want the exact opposite. Most large companies have the extra cash to spend in the case that a runwaway auto-scale was in error, but on the other hand, completely shutting down operations whenever a traffic spike happens could resort in millions of lost revenue.
>However, searching around it seems like I can only get alerts when a $$$ threshold is passed, but AWS won't take any action to stop computing or anything. Please prove me wrong.
The general advice is to use the various kinds of usage alerts (billing alerts, forecasts, etc) to trigger Lambda functions that shut down your instances as you desire. It takes a little configuration on your part, but again, AWS intentionally errs on the side of not automatically turning off your instances unless you specifically tell it to.
Great companies find ways to help their customers thrive.
People make mistakes with transferring money in the millions of dollars all the time, and it's not uncommon for people to be just like "oops, back that out". It's obviously going to be in the news when that doesn't happen though.
It does not have to be all or nothing. You could for example setup separate account per department and/or purpose and impose hard cap on spending for experimentation, but not on production.
What some people are asking for--and it's a reasonable use case but one that AWS, somewhat understandably, isn't really focused on--is: "Burn it all down if you have to, including deleting databases, but no way no how charge me a penny more than $100/month (or whatever my set limit is)."
That means any data getting lost as a result of that limit is data that they weren't guaranteeing in the first place. You might not be able to actually read your EBS volumes, S3 buckets or Aurora tables without increasing the spending limit or otherwise committing more funds, but it won't go away that second, and you would have enough time to fix it (worst case - wait until next month; you did budget that already).
Alternatively: assign each resource to a pool, and monthly spending limits to each pool. Give your EBS/S3 $1000/month, and your R&D-pet-project-that-may-accidentally-spawn-a-billion-machines $50/month.
And, as you say, it makes sense to have a pool--whether it's your whole AWS account or not--where you can turn on the "burn it all down" option if you want to.
For example, you shut down the ability to launch anything in a particular region easily - but assume you specifically want to exceed a default limit - you can call speak with your rep and have any of your limits set to whatever you want