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From Marius Soutier <mps....@gmail.com>
Subject Re: SparkSQL performance
Date Mon, 03 Nov 2014 10:31:26 GMT
I did some simple experiments with Impala and Spark, and Impala came out ahead. But it’s
also less flexible, couldn’t handle irregular schemas, didn't support Json, and so on.

On 01.11.2014, at 02:20, Soumya Simanta <soumya.simanta@gmail.com> wrote:

> I agree. My personal experience with Spark core is that it performs really well once
you tune it properly. 
> 
> As far I understand SparkSQL under the hood performs many of these optimizations (order
of Spark operations) and uses a more efficient storage format. Is this assumption correct?

> 
> Has anyone done any comparison of SparkSQL with Impala ? The fact that many of the queries
don't even finish in the benchmark is quite surprising and hard to believe. 
> 
> A few months ago there were a few emails about Spark not being able to handle large volumes
(TBs) of data. That myth was busted recently when the folks at Databricks published their
sorting record results. 
>  
> 
> Thanks
> -Soumya
> 
> 
> 
> 
>  
> 
> On Fri, Oct 31, 2014 at 7:35 PM, Du Li <lidu@yahoo-inc.com> wrote:
> We have seen all kinds of results published that often contradict each other. My take
is that the authors often know more tricks about how to tune their own/familiar products than
the others. So the product on focus is tuned for ideal performance while the competitors are
not. The authors are not necessarily biased but as a consequence the results are.
> 
> Ideally it’s critical for the user community to be informed of all the in-depth tuning
tricks of all products. However, realistically, there is a big gap in terms of documentation.
Hope the Spark folks will make a difference. :-)
> 
> Du
> 
> 
> From: Soumya Simanta <soumya.simanta@gmail.com>
> Date: Friday, October 31, 2014 at 4:04 PM
> To: "user@spark.apache.org" <user@spark.apache.org>
> Subject: SparkSQL performance
> 
> I was really surprised to see the results here, esp. SparkSQL "not completing"
> http://www.citusdata.com/blog/86-making-postgresql-scale-hadoop-style
> 
> I was under the impression that SparkSQL performs really well because it can optimize
the RDD operations and load only the columns that are required. This essentially means in
most cases SparkSQL should be as fast as Spark is. 
> 
> I would be very interested to hear what others in the group have to say about this. 
> 
> Thanks
> -Soumya
> 
> 
> 


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