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From Jimmy Lin <jimmy...@umd.edu>
Subject Re: Coordination between Mapper tasks
Date Sat, 28 Mar 2009 15:47:48 GMT
Hmmm... sounds odd. Given the same memcached servers (config), the 
hashing should be consistent.

FYI, all code for the experiments described in that tech report is in 
cloud9, the library I use for teaching my courses.  Download at:

http://www.umiacs.umd.edu/~jimmylin/

Hope this helps! (Let me know off list if you need more details)

-Jimmy

Stuart White wrote:
>> You might want to look at a memcached solution some students and I worked
>> out for exactly this problem.
> 
> Thanks, Jimmy!  This paper does exactly describe my problem.
> 
> I started working to implement the memcached solution you describe,
> and I've run into a small problem.  I've described it on the
> spymemcached forum:
> 
> http://groups.google.com/group/spymemcached/browse_thread/thread/7b4d82bca469ed20
> 
> Essentially, it seems the keys are being hashed inconsistently by
> spymemcached across runs.  This, of course, will result in
> inconsistent/invalid results.
> 
> Did you guys run into this?  Since I'm new to memcached, I'm hoping
> that this is simply something I don't understand or am overlooking.
> 

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