title: In Spark 1.6 how to avoid data skew issue and evenly distribute the data
body: <p>Hi I am reading a sequence file containing json format record, when reading the json record converting into Dataframe  causing data skew issue as you can see form Spark UI screen shot. How to avoid this data skew issue ?</p>
  
  <pre><code>val src = sc.sequenceFile(FilePath, classOf[Text], classOf[Text] )
  val df = sqlCntxt.read.json(src)
  </code></pre>
  
  <p>261 Completed tasks                 </p>
  
  <pre><code>Metric  Min 25th Percentile Median  75th Percentile Max
  Duration    47 ms   0.1 s   5 s 25 s    **1.0 min**
  GC Time 0 ms    0 ms    0 ms    0.1 s   0.7 s
  Input Size/ Records 438.0 B/1   1013.0 B /2 1776.0 B/ 12    128.2 MB / 277608   **128.5 MB / 1162416**
  Shuffle Write size/Records  240.0 B/1   446.0 B /1  509.0 B / 1 622.0 B /1  **2.3 KB /1**
  </code></pre>