How does Google App Engine data store scale with Polls -

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if have poll application on gae being simultaneously updated across several continents, given app has been replicated across google infrastructure, data store keep accurate count? need design consideration such application?

applications aren't replicated across google's infrastructure worldwide. if you're using master-slave datastore (the default until recently), consistent, , reads served single datacenter (with data replicated datacenter backup, not serve requests ordinarily). hr datastore, eventual consistency outside of transactions, believe of data in north america , latency isn't anywhere near might expect if data being stored on different continents (and, in case, can use transactions).


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