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From Fabian Hueske <fhue...@gmail.com>
Subject Re: State Descriptors / Queryable State Question
Date Thu, 26 Jan 2017 14:21:45 GMT
Hi Joe,

working on a KeyedStream means that the records are partitioned by that
key, i.e., all records with the same key are processed by the same thread.
Therefore, only on thread accesses the state for a particular key.
Other tasks do not have read or write access to the state of other tasks.

Best, Fabian

2017-01-26 14:10 GMT+01:00 Joe Olson <technology@nododos.com>:

> If I have a keyed stream going in to a N node Flink stream processor, and
> I had a job that was keeping a count using a ValueStateDescriptor (per
> key), would that descriptor be synchronized among all the nodes?
>
> i.e. Are the state descriptors interfaces (ValueStateDescriptor,
> ListStateDescriptor) threadsafe?If I expose that descriptor via the
> RunTimeContext, will I get a consistent value back from each of the nodes?
>
> Thanks!
>
>

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