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From MANISH SINGLA <coolmanishh...@gmail.com>
Subject Re: why quick sort when spill map output?
Date Mon, 28 Feb 2011 13:04:28 GMT
one of the major reasons of using quicksort would be that quicksort
can easily be parallalized...due to its divide and conquer nature

On Mon, Feb 28, 2011 at 6:06 PM, James Seigel <james@tynt.com> wrote:
> Sorting out of the map phase is core to how hadoop works.  Are you asking why sort at
all?  or why did someone use quick sort as opposed to _____sort?
>
> Cheers
> James
>
>
> On 2011-02-28, at 3:30 AM, elton sky wrote:
>
>> Hello forumers,
>>
>> Before spill the data in kvbuffer to local disk in map task, k/v are
>> sorted using quick sort. The complexity of quick sort is O(nlogn) and
>> worst case is O(n^2).
>> Why using quick sort?
>>
>> Regards
>
>

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