Consequences of an infinite loop on Google App Engine? [closed]

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I am not a Google App Engine user. However, I understand you're billed for CPU time and other resources. Wha开发者_运维技巧t are the consequences if you happen to create an infinite loop? Will Google ever terminate it, or will you have to do it yourself manually somehow?

I'm a hobbyist developer worried about a small error that might end up costing hundreds.

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(I'm a Google employee but have little experience with AppEngine. Please don't consider this an "official" response.)

I'm guessing you're using the Java servlet API - if not, please specify.

From the AppEngine servlet docs:

A request handler has a limited amount of time to generate and return a response to a request, typically around 30 seconds. Once the deadline has been reached, the request handler is interrupted.

I don't know how/whether this occurs in a tight-loop which wouldn't allow the VM to interrupt it in "normal" Java.

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While Jon handled the low level case of an infinite loop, there could also be a situation where one of your handlers is called repeatedly an excessive amount of times - perhaps you accidentally configure something to back up your entire datastore every second instead of once a day. Theoretically, you could use up a lot of resources, even in 30 second chunks. However, you would still not be in danger of racking up a huge amount of charges. You have the option of setting a limit on how much you want to "spend" per day. If you have no quota left, your app will return an error, not put you into debtor's prison.

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Google AppEngine imposes a limit on how long a request may take before it is terminated,

There is a roughly 30 second limit imposed on how long a request must take before it is terminated. However, shortly before the process is terminated, a DeadlineExceededError exception will be thrown.

Additionally there are per-minute quotas to prevent the application from consuming too much quota in a short period of time. It is very unlikely that your application will exceed the per-minute quota under normal conditions, but, if needed an increase to this quota can be requested.