Spark 2.2 will support the recommend-all methods in ML.

Also, both ML and MLLIB performance has been greatly improved for the
recommend-all methods.

Perhaps you could check out the current RC of Spark 2.2 or master branch to
try it out?

N

On Thu, 8 Jun 2017 at 17:18, Sahib Aulakh [Search] ­ <
sahibaul...@coupang.com> wrote:

> Many thanks for your response. I already figured out the details with some
> help from another forum.
>
>
>    1. I was trying to predict ratings for all users and all products.
>    This is inefficient and now I am trying to reduce the number of required
>    predictions.
>    2. There is a nice example buried in Spark source code which points
>    out the usage of ML side ALS.
>
> Regards.
> Sahib Aulakh.
>
> On Wed, Jun 7, 2017 at 8:17 PM, Ryan <ryan.hd....@gmail.com> wrote:
>
>> 1. could you give job, stage & task status from Spark UI? I found it
>> extremely useful for performance tuning.
>>
>> 2. use modele.transform for predictions. Usually we have a pipeline for
>> preparing training data, and use the same pipeline to transform data you
>> want to predict could give us the prediction column.
>>
>> On Thu, Jun 1, 2017 at 7:48 AM, Sahib Aulakh [Search] ­ <
>> sahibaul...@coupang.com> wrote:
>>
>>> Hello:
>>>
>>> I am training the ALS model for recommendations. I have about 200m
>>> ratings from about 10m users and 3m products. I have a small cluster with
>>> 48 cores and 120gb cluster-wide memory.
>>>
>>> My code is very similar to the example code
>>>
>>> spark/examples/src/main/scala/org/apache/spark/examples/mllib/MovieLensALS.scala
>>> code.
>>>
>>> I have a couple of questions:
>>>
>>>
>>>    1. All steps up to model training runs reasonably fast. Model
>>>    training is under 10 minutes for rank 20. However, the
>>>    model.recommendProductsForUsers step is either slow or just does not work
>>>    as the code just seems to hang at this point. I have tried user and 
>>> product
>>>    blocks sizes of -1 and 20, 40, etc, played with executor memory size, 
>>> etc.
>>>    Can someone shed some light here as to what could be wrong?
>>>    2. Also, is there any example code for the ml.recommendation.ALS
>>>    algorithm? I can figure out how to train the model but I don't understand
>>>    (from the documentation) how to perform predictions?
>>>
>>> Thanks for any information you can provide.
>>> Sahib Aulakh.
>>>
>>>
>>> --
>>> Sahib Aulakh
>>> Sr. Principal Engineer
>>>
>>
>>
>
>
> --
> Sahib Aulakh
> Sr. Principal Engineer
>

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