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From Benjamin Black...@b3k.us>
Subject Re: Question about hinted handoff
Date Sat, 10 Jul 2010 22:27:04 GMT
You constructed a pathological case and then got confused at the result.

Consider instead a realistic case: RF=3, CL=QUORUM.  Writes should go
to all of A, B, and C.  B is down when the write request arrives, so
does not acknowledge the it.  A and C acknowledge the write.  Since
quorum is achieved, success is returned to the client and a hint for B
is written to A (since A is already a replica and since 0.6 hints go
to existing replicas rather than non-replica nodes).  When B comes
back up, it requests hints, A sends the missed write, bringing B back
in sync.


b

On Thu, Jul 8, 2010 at 7:04 AM, ChingShen <chingshenchen@gmail.com> wrote:
> If so, when does hinted handoff work?
>
> On Thu, Jul 8, 2010 at 9:55 PM, Anty <anty.rao@gmail.com> wrote:
>>
>>
>> On Thu, Jul 8, 2010 at 4:11 PM, ChingShen <chingshenchen@gmail.com> wrote:
>>>
>>> Hi all,
>>>
>>>   Please consider this case: (RF=1, CL=ONE)
>>>
>>>   1. I have A, B and C nodes.
>>>   2. A node is a coordinator node, it sends a request to B node to do
>>> write operation.
>>>   3. B node is down during write operation, so return failure message to
>>> client, and write a hint to C node.
>>
>> I think node A will return failure message to client.
>> and will not write a hint to C node.
>>
>>>
>>>   4. B node comes back up, then C node forwards the data to it.
>>>   5. B node own data right now, although the write operation is failure.
>>>
>>>   Correctly?
>>>
>>> Thanks.
>>>
>>> Shen
>>
>>
>>
>> --
>> Best Regards
>> Anty Rao
>
>
>

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