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From Mike Carey <>
Subject Re: Trio: AsterixDB, Spark and Zeppelin.
Date Thu, 11 Aug 2016 21:42:48 GMT

1. Interesting problem!  That tempts me to suggest that your target 
dataset of Tweets should make heavier use of AsterixDB's open typing 
capabilities.  You could make the schema for it only have the "sure 
thing" fields, and let the variable parts be self-describing.  Have you 
experimented with that?

2. This seems like two issues.  First, there's an algorithm that needs 
to be scale tested.  That seems like it could be done on Spark without 
forming an (unnecessary?) immediate dependency on AsterixDB's 
connector.  Second, there's the desire/need to feed that algorithm (when 
it's working) data from AsterixDB so that social/health data scientists 
can explore how it works on different data subsets.  That indeed has a 
dependency.  How about two steps, first step first for the student?  
(I'm assuming, possibly wrongly, that neither step has been taken yet.)

3a. Could we get a concise list of those queries and the times and 
expectations in a little shared document somewhere (or in a JIRA 
issue)?  As it turns out, AsterixDB's "worst aggregate query" is the AQL 
equivalent of SELECT COUNT(*) FROM Tweets - because it can only run that 
query by scanning the data.  While it does it in parallel, that's still 
very slow compared to what you might want.  (The reason is that the 
Tweets are stored in a primary-key'ed BTree in AsterixDB and in order to 
know how many there are, you have to inspect the leaves.) This would be 
necessary anyway if the query was anything other than COUNT(*) without a 
predicate - but in that (lone) case you end up getting a "worst case" 
time compared to what you might hope for.  There are engineering 
solutions to make unfiltered counting run faster, but it's not obvious 
how much time one would want to invest in that.  (If you could unleash 
Kevin on that we could discuss the work he'd need to do - that would be 
one model - but it feels like that's not the "normal use case" query, so 
I'm not sure that'd be the right investment for anyone.)

3b. Could we see some of the common ML queries here, to prepare accordingly?




PS - Any chance you could participate in the Friday 10-11 status calls?  
Or perhaps we should set up a separate weekly 1/2 hour for SDSC status 
calls?  I think it would be really good for us to view SDSC as the 
"premier showcase customer" (and transitively, UCLA) make sure we have a 
better (less lossy/noisy) connection in place to make sure it's a big 
success, and I think weekly would be the right frequency to operate the 
connection at, if that works for you all.

On 8/10/16 5:02 PM, Gupta, Amarnath wrote:
> Mike:
> The timetable actually comes from Sean and Wei, whom we are trying to 
> serve through our efforts at SDSC. There are three issues we are 
> trying to handle right now.
> 1. The 2015 Twitter data set, which UCLA needs access to, is large, 
> and we often discover that the actual schema shifts over time, causing 
> a cascade of failures that Kevin and Ian are sorting out.
> 2. While we originally put Spark integration later in our timetable, 
> Wei's group needs access to it now. I spoke to the student and she has 
> an algorithm that is waiting to be tested for larger scale data.
> 3. *Some* aggregate queries, curiously take a really long time. Ian is 
> also aware of this. Since aggregate queries are very common for 
> machine learning explorations, I would feel better if these queries 
> execute within a reasonable time.
> I appreciate your comment about getting higher visibility of SDSC as 
> an early adopter of AsterixDB. Kevin has been spending a lot of time 
> with AsterixDB and fielding requirements we all dump on him. I am 
> hoping that we can actually achieve something concrete through this 
> effort.
> Thanks,
> Amarnath
> ------------------------------------------------------------------------
> *From:* Michael Carey []
> *Sent:* Wednesday, August 10, 2016 4:41 PM
> *To:*;
> *Cc:* Gupta, Amarnath; Sean Young
> *Subject:* Re: Trio: AsterixDB, Spark and Zeppelin.
> Kevin,
> Thanks!  That helps a lot.  Now what we need to know (possibly above 
> your pay grade :-)) is what the timetable is for UCLA (i) wanting to 
> get the results of your assessment of how well what's there works and 
> meets their needs and (ii) wanting to put stuff into production (and 
> at what scale).  I don't anticipate the review and merging taking 
> forever, but this will be Wail's first AsterixDB code contribution - 
> last I knew he was addressing initial reviewing comments (and I'm not 
> sure if all reviews are done yet) - but I think we next need to ask 
> UCLA/Sean/Amarnath for the timetable info.
> Cheers,
> Mike
> On 8/10/16 1:33 PM, Coakley, Kevin wrote:
>> Mike,
>> UCLA wanted a way to do use Spark’s Machine Learning packages with data stored
in AsterixDB. We started looking at the Spark connector as way to access the data in AsterixDB
directly instead of having to export the data from AsterixDB to a file and import the file
in Spark. I don’t know how this is fits into Amarnath’s projects, I was just following
up on a request from UCLA to see what would be involved in providing this Spark connector
to others.
>> The current status is: I have the Spark connector working in a test environment with
the queries provided by Wail. I was planning on loading a small amount of data into the test
AsterixDB server with the Schema Inferencer code and running my own queries, but I have not
had time yet. The issue with providing others with access to the Spark connector is the version
of AsterixDB that we are running that contains the Twitter data does not have the Schema Inferencer
code and therefor will not work with the Spark connector.
>> I don’t believe SDSC would want to update the AsterixDB servers that contain the
Twitter data with the Schema Inferencer code until after it has been approved by you and merged
into the master branch. However, even after the Schema Inferencer code has been merged into
the master branch, we wouldn’t have it ready of people to use right away.
>> I offered to load a small subset of the data from our main servers into my test environment
that has a working Spark connector for UCLA to test, but it sounds like they misunderstood
my offer.
>> I would be happy to help you test the Schema Inferencer and Spark connector if you
have specific items that you want me to check, I can also give others that you select access
to test environment so they can run tests themselves. Otherwise, I will respond here if I
discover any issues.
>> My current test environment is Zeppelin with the Spark connector on server A, AsterixDB
with the Schema Inferencer code on server B and a Spark 1.6.0 cluster running on servers C,
D and E.
>> -Kevin
>> On 8/10/16, 9:36 AM, "Mike Carey"<>  wrote:
>>      Kevin,
>>      Q:  Could you chime back in here - please 'cc' the user list - with a
>>      brief (maybe one paragraph) summary of what you are actually trying to
>>      do at the moment and what its current status is?  (And your timeframe,
>>      etc.?)
>>      My impression until yesterday was that you were slowly/leisurely
>>      exploring the new Spark connector to AsterixDB that Wail worked on -
>>      essentially as his first "beta" user - and that things were moving at
>>      the pace you wanted (and were setting).  As an early adopter, I was also
>>      under the impression that you were using his branch for your
>>      explorations, while he was addressing code review comments, etc.
>>      However, when I arrived back home in OC after a trip yesterday, I was
>>      the recipient of a message (via a back channel) warning me that there
>>      was a blocking issue at SDSC that UCI wasn't being attentive to, one
>>      that had AsterixDB on the brink being given up on by the UCLA folks, and
>>      that we'd better get on it or....  (Meanwhile I had not heard any such
>>      thing from UCLA directly; I was not aware of any blocking Spark issues
>>      for SDSC nor of any transitively blocking implications for UCLA, and it
>>      still doesn't look from what I see below like there was one.)
>>      I think that we need to have SDSC's activities be much more visible here
>>      - likewise for UCLA's - so that the Apache AsterixDB community has much
>>      better visibility into the goals, activities, progress, and problems of
>>      our early adopters.  The community wants users to be successful!  It
>>      will be much more effective (and healthy and productive) if we all know
>>      what's going on and it is clear to all how each of those things are going.
>>      Thanks!
>>      Mike
>>      On 8/10/16 8:36 AM, Wail Alkowaileet wrote:
>>      > Hi Kevin,
>>      >
>>      > Cool!
>>      > Please let me know if you need any assistance.
>>      >
>>      > On Aug 8, 2016 1:42 PM, "Coakley, Kevin"<>  wrote:
>>      >
>>      >> Hi Wail,
>>      >>
>>      >> I figure out the problem, AsterixDB was configured for The
>>      >> notebook at
>>      >> connector/blob/master/zeppelin-notebook/asterixdb-spark-example/note.json
>>      >> ran successfully once I recreated the AsterixDB instance to use the
>>      >> external IP.
>>      >>
>>      >> I have not ran any of my own queries but I did get both of the examples
>>      >>  to run
>>      >> successfully.
>>      >>
>>      >> Thank you!
>>      >>
>>      >> -Kevin
>>      >>
>>      >>
>>      >>
>>      >> On 8/3/16, 10:23 AM, "Wail Alkowaileet"<> 
>>      >>
>>      >>      One more thing:
>>      >>      Can you paste your cluster configuration as well?
>>      >>
>>      >>      Thanks
>>      >>
>>      >>     (ETC ETC ETC deleted)

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