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From Rajkumar S <rajkum...@gmail.com>
Subject Re: Slow Map Reduce
Date Fri, 23 Oct 2009 11:18:41 GMT
Hi,

Thanks, I had caught this bug and fixed it in the map, but did not
update the mail. I just wanted the sum. but right now I am not using a
reduce function just a map. Even for that I am not getting a result.

Any way I am just learning the ropes so might take some  time before I
figure out the stuff :)

raj

On Fri, Oct 23, 2009 at 6:40 AM, Seggy Umboh <seggy.umboh@gmail.com> wrote:
> It looks like you just want to find out how many rows were emitted? That
> would just be the typical sum right?
> return sum(values);
>
>
>
> js> var v = 6
> js> 0 + v.length
> NaN
>
>
>
> On Wed, Oct 21, 2009 at 11:45 PM, Rajkumar S <rajkumars@gmail.com> wrote:
>
>> On Wed, Oct 21, 2009 at 9:48 PM, Paul Joseph Davis
>> <paul.joseph.davis@gmail.com> wrote:
>> > I suspect "return values;" is the culprit here. That's pretty much
>> guranteed
>> > to cause you problems as the data grows recursing up the tree. 0.10.0
>> even
>> > detects this and throws an error to avoid precisely this issue.
>> >
>> > It's been discussed a couple times on the list but my stomach is
>> rumbling.
>>
>> That reduce function used in that log was the following.
>>
>> function(keys, values, rereduce)
>> {
>>    length = 0;
>>    if (rereduce){
>>        for(var v = 0; v < values.length; v++){
>>            length = length + v.length;
>>        }
>>    } else {
>>        length = values.length;
>>    }
>>    return length;
>> }
>>
>> The reduce function should returns a single integer and not cause data
>> to grow. Let me try with simpler map with no reduce and will report
>> the results.
>>
>> with regards,
>> raj
>>
>

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