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0 pointsnl15y ago0 comments

In my experience "instability" with GAE means you are pushing it beyond where it wants to go. If you a have code that just completes within the timeout, then guess what? When the system is under load it isn't going to complete.

You can use all kinds of techniques to protect your application from things like variable datastore performance. For example, nowdays I usually use a pattern where user-facing servlets only ever read from the datastore - all updates go via a taskqueue, which means that even if the datastore is in maintenance mode the updates will eventually be applied.

GAE isn't for everyone, but the first step to getting the most out of it is accepting it isn't anything like a typical frontend plus database architecture.

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mmastrac15y ago

Late September was bad for the datastore. We were seeing latency on simple queries vary from 50ms up to 5s. These were simple properly-value queries as well. This was fixed in early October I think, and a recent bit of maintenance brought latencies down even further. The datastore is now extremely fast and rarely errors out.

We (http://gri.pe) are still happy on AppEngine, even though September was rough.

grandalf15y ago

Very true. The datastore unreliability was a real nightmare. I was getting periods of 60 seconds where it was unusable...

But it does appear to be fixed now.

nischalshetty15y ago

The Datastore problems have indeed been fixed and things have been smooth since the fix.

fauigerzigerk15y ago

" If you a have code that just completes within the timeout, then guess what? When the system is under load it isn't going to complete."

Unless the platform scales as it should, which is the whole point of accepting all the limitations. If there are tight and hard limits on request timeout, then there must be equally stringent guarantees provided by the underlying platform. "We're working on it" is just not enough under these conditions.

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