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MapReduce >> mail # user >> How to change topology


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Shinichi Yamashita 2012-10-08, 13:23
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Steve Loughran 2012-10-09, 08:22
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Steve Loughran 2012-10-09, 19:17
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Re: How to change topology
On Tue, Oct 9, 2012 at 12:17 PM, Steve Loughran <[EMAIL PROTECTED]>wrote:

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>
> On 9 October 2012 16:51, Shinichi Yamashita <[EMAIL PROTECTED]> wrote:
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>> Hi Steve,
>>
>> Thank you for your reply.
>>
>>
>> > no, it's the Namenode and JobTracker that needs to be restarted;
>> > they are the bits that care where the boxes are.
>>
>> I confirmed it in my cluster, and I understood it as follows.
>> First, the resolved node information is recorded in ConcurrentHashMap.
>> Next same node toplogy decision, HashMap data is given priority to over a
>> script.
>> The HashMap data become invalid by restart of NameNode and JobTracker.
>>
>
> That's right. There's been lots of discussion on adding live topology
> resetting.
>

For what it's worth, there is at least one Hadoop derived distribution
which has live topology resetting already.

I can follow up offline with anyone who wants more information.
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Shinichi Yamashita 2012-10-10, 15:19