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Re: [dist-obj] Seven Fallacies Reference
> Not really. The two-phase/three-phase commit protocol requires an
> assumption about "benign" characteristics of underlying request-reply
> Let's take two-phase commit for instance for the scenario. (3-Phase is
> similar, only marginally improve the reliability)
> The robot acked, the dispatcher got it, and said "commit", the robot didn't
> get the commit,
>then the dispatcher thought it was done, cross out the task,
why would this happen ? Transactions theory is based on the assumption of a
reliable network -- and of course transactions would only be used on a
reliable network for tasks that need to be done reliably ! I do not understand
why would someone run a transaction system on top of lossy wireless links ?
I do not see how link failures in mobile networks are any different from link
failures in traditional wired distributed systems ?
> Multi-phase commit protocols do not solve the problem, fundamentally
> because of the impossibility of consensus when arbitrary link failures are
Yes, in a system where links are unreliable, the hosts are unreliable and
there is no synchronization service ---- is that what a transaction based
mobile system would look like ? I don't think so ...
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