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watchful_moose | 3 months ago

Yep, a decent canary mechanism should have caught this. There's a trade off between canarying and rollout speed, though. If this was a system for fighting bots, I'd expect it to be optimized for the latter.

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kevincox|3 months ago

I'm shocked that an automatic canary rollout wasn't an action item. Pushing anything out globally is a guaranteed failure again in the future.

Even if you want this data to be very fresh you can probably afford to do something like:

1. Push out data to a single location or some subset of servers.

2. Confirm that the data is loaded.

3. Wait to observe any issues. (Even a minute is probably enough to catch the most severe issues.)

4. Roll out globally.

hnarn|3 months ago

Presumably optimal rollout speed entails something like or as close to ”push it everywhere all at once and activate immediately” that you can get — that’s fine if you want to risk short downtime rather than delays in rollout, what I don’t understand is why the nodes don’t have any independent verification and rollback mechanism. I might be underestimating the complexity but it really doesn’t sound much more involved than a process launching another process, concluding that it crashed and restarting it with different parameters.

kevincox|3 months ago

I think they need to strongly evaluate if they need this level of rollout speed. Even spending a few minutes with an automated canary gives you a ton of safety.

Even if the servers weren't crashing it is possible that a bet set of parameters results in far too many false positives which may as well be complete failure.