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From Josh Elser <>
Subject Re: Assignment Overview Doc
Date Thu, 13 Aug 2015 16:03:46 GMT
Yes, I omitted the session ID intentionally due to confusion of "what 
the heck is that random string". I thought I had mentioned that there is 
a uniqueness string on there to identify instances of servers on the 
same host and port, but maybe I dropped that out in the end.

Ultimately, it's not really relevant for the assignment discussion, 
assignment just cares about a unique instance of a server. I'll see if I 
can maybe clarify that.

Thanks for taking the time to read and send back some feedback!

Keith Turner wrote:
> i noticed the document uses<server>:<port>   to identify tablet servers in
> some places.   Something more specific is used in the code
> :<server>:<port>:<zk session id>.   This last dimension allows the
> to distinguish between two different instances of a tserver running at the
> same host and port at different times.
> On Wed, Aug 12, 2015 at 12:39 PM, Josh Elser<>  wrote:
>> I had some HBase friends ask me for a design document on how Tablet
>> assignment in Accumulo works. Their assignment logic continues to be a pain
>> point and there's been a lot of confusion about wanting to use FATE for
>> assignments (even moreso when I would tell people: no, that's unnecessary).
>> Since we didn't have a good reference document (I'm guessing because it
>> was designed prior to the initial import of code), I took the time to write
>> one up based on my understanding of the code and some pointers from Eric.
>> Think this deserves a place in our documentation somewhere? Seems like
>> it's a good reference sheet to have lying around, but I'm not sure where
>> best it'd be stored.
>> Huge thanks to Eric for his pointers and editing.
>> - Josh

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