Hello Pedro Spark core is a general purpose in memory analytics engine. Adding to spark core things like sparkSQL or SparkML you can do many interesting analytics or Datascience modelling, in a programatic or sql fashion. Maybe this tutorial can help you in your first steps. http://hortonworks.com/hadoop-tutorial/hands-on-tour-of-apache-spark-in-5-minutes/ http://hortonworks.com/blog/data-science-hadoop-spark-scala-part-2/ ... View more

Hello Sumit Increasing the zookeeper session timeout is often a quick first fix to GC pause "killing" in Hbase. In the longer run If you have GC pauses is because your process is trying to find memory. There can be architectural approaches to this problem: For example does this happen during heavy writes loads in which case you consider doing bulk load when possible. You can also look at your hbase configuration what is your overall allocated memory for Hbase and how is distributed for writes and reads. Do you flush your memstore often, does this lead to many compactions? Lastly you can look at GC tuning. I won't dive into this one but Lars has done a nice introduction blog post on this here:http://hadoop-hbase.blogspot.ie/2014/03/hbase-gc-tuning-observations.html Hope any of this helps ... View more

Hello Kiran Spark is not yet a GA feature in Hive, still very much in dev phase. You can however use SparkSQL to issue queries in a hive context to use Hive tables. ... View more

Hello arunkumar As a general rule it will come back to what you are trying to achieve and how you want to service data. Remember that Hbase's performance is directly derived from the rowkey and hence how you access data. Hbase will split up data in regions served by region servers and on a lower level data will be split by Column Family. A single entry however will be served by the same region. At high level the difference between tall-narrow and flat-wide comes back to scans vs gets. Since Hbase has an ordered on the rowkey storage policy and full scans are costly. A Tall-narrow approach would be to have a more complex rowkey giving adjacency of similar elements and allowing to do focused scans for logical group of entries. A Flat-wide approach would ahve much more information in the entry itself, you "get" the entry through the rowkey and the entry would have sufficient information to do your compute or answer your query. hope this helps ... View more