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From Paul Prescod <p...@prescod.net>
Subject Re: Memcached protocol?
Date Mon, 05 Apr 2010 04:22:15 GMT
On Sun, Apr 4, 2010 at 8:48 PM, Benjamin Black <b@b3k.us> wrote:
> ...
>
> It gives vector clocks, but that does not mean you have a global
> counter you can use as you are describing.  In particular, the "read
> after write to trigger read repair" in cases where read repair is
> actually required is most likely to result in a counter being updated
> several times, with the last value seen by multiple clients, rather
> than each client getting a unique value along the way (unless I am
> misunderstanding what you are describing).  Is that the behavior you
> want?

Yes, as long as all of them converge on a "correct" number eventually,
I think that's the goal. Imagine you are counting site visitors.
Writes will come in left and write and then the conflict resolution
will do the summation to really get the right count. I don't care if
any particular client sees intermediate values, nor that they see
unique values.

 Paul Prescod

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