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Zookeeper, mail # dev - what happen in case of zxid overflow?


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Re: what happen in case of zxid overflow?
Mahadev Konar 2011-10-14, 07:24
Alex,
 If you just started your 3 servers, the one with highest id is picked the leader.

thanks
mahadev

On Oct 14, 2011, at 12:01 AM, 박영근(Alex) wrote:

> Mahadev,
>
> Question about leader election is that who is elected when composing *the
> first* quorum;
> I found that server myId is used in updateProposal() methd of
> FastLeaderElection.lookForLeader().
> So, I guess that at the first time a zkserver who has middle myId becomes a
> leader.
> (I had already read attached paper)
>
> And, I agree with your comments about both zxid and cversion;
> I had same thought like your comments and just want to make it confirmed.
>
> Thanks,
> Alex
>
> 2011/10/14 Mahadev Konar <[EMAIL PROTECTED]>
>
>> Alex,
>> The zxid is a long and the likelihood of it overflowing is pretty
>> low. The cversion though is an int. I think we had a jira to upgrade
>> to long, but its not been fixed yet. Though being an int is not that
>> terrible since you'd have to add/delete billion children to get it to
>> overflow, which probably is highly unlikely.
>>
>> About leader election its probably much more detailed than just the
>> id. You can find more details in :
>>
>> http://research.yahoo.com/files/ZooKeeper.pdf
>>
>> thanks
>> mahadev
>>
>> On Thu, Oct 13, 2011 at 6:27 PM, 박영근(Alex) <[EMAIL PROTECTED]> wrote:
>>> Hi, All
>>>
>>> Is there any defense logic for both zxid and znode Cversion overflow?
>>>
>>> And, does a server that has middle myId among serverIds becomes a leader
>> at
>>> initial leader election right?
>>>
>>> Thanks
>>>
>>> Alex
>>>
>>