mapreduce - Spark : How to design streaming with spark? -

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current architecture

mysql database rest api abstraction.

the problem

mysql not scaling various reasons including data model design hard fix.

proposed architecture

using cassandra nosql backend , using spark in memory computation engine along spark streaming.

questions

  • how cassandra's consistency ? decision directly use kafka streams carries real time information cassandra , use spark sql query data.
  • if consistency above good, how rdd's designed around since immutable.do create new rdd's ?
  • an alternative design migrate data mysql cassandra , use kafka directly send messages spark handles in real time , use downstream systems hand on data cassandra on time.

in points 1&2 consistency dependant upon cassandra , in point 3 tied spark.

which design better ? can throw light on this.


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