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From Andrei Savu <savu.and...@gmail.com>
Subject Re: election recipe
Date Sat, 04 Sep 2010 18:16:54 GMT
You should also be careful how you handle connection loss events. The
leader should suspend itself and re-run the election process when the
connection is reestablished.

On Sat, Sep 4, 2010 at 8:37 AM, Mahadev Konar <mahadev@yahoo-inc.com> wrote:
> Hi Eric,
>  As Ted and you yourself mentioned its mostly to avoid herd affect.  A herd
> affect would usually mean 1000¹s of client notified of some change and would
> try creating the same node on notification.  With just 10¹s of clients you
> don¹t need to worry abt this herd effect at all.
>
> Thanks
> mahadev
>
>
> On 9/2/10 3:40 PM, "Ted Dunning" <ted.dunning@gmail.com> wrote:
>
>> You are correct that this simpler recipe will work for smaller populations
>> and correct that the complications are to avoid the herd effect.
>>
>>
>>
>> On Thu, Sep 2, 2010 at 12:55 PM, Eric van Orsouw
>> <eric.van.orsouw@gmail.com>wrote:
>>
>>> Hi there,
>>>
>>>
>>>
>>> I would like to use zookeeper to implement an election scheme.
>>>
>>> There is a recipe on the homepage, but it is relatively complex.
>>>
>>> I was wondering what was wrong with the following pseudo code;
>>>
>>>
>>>
>>> forever {
>>>
>>>    zookeeper.create -e /election <my_ip_address>
>>>
>>>    if creation succeeded then {
>>>
>>>        // do the leader thing
>>>
>>>    } else {
>>>
>>>        // wait for change in /election using watcher mechanism
>>>
>>>    }
>>>
>>> }
>>>
>>>
>>>
>>> My assumption is that the recipe is more elaborate to the eliminate the
>>> flood of requests if the leader falls away.
>>>
>>> But if there are only a handful of leader-candidates ,than that should not
>>> be a problem.
>>>
>>>
>>>
>>> Is this correct, or am I missing out on something.
>>>
>>>
>>>
>>> Thanks,
>>>
>>> Eric
>>>
>>>
>>>
>>>
>>
>
>



-- 
Andrei Savu -- http://www.andreisavu.ro/

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