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Re: Swift Consistency Guarantees?
Mark Nottingham asked:
>Why not just use
> Cache-Control: no-cache?
>That way, intervening caches will do the right thing too...
Even with no caching anywhere you still have N replicas (typically three) that will be updated in an arbitrary order,
and clients that read from any one of those replicas.
Unless you implement a draconian global locking scheme there is nothing you can do to prevent a client from reading
a copy that has just been rendered obsolete by another client completing the edit of the (N+1)/2th replica.
If the goal is to validate with all N servers then this should be a special transaction. The benefits of caching should remain
In place for typical reads.