title: spark dataframe save as partitioned table very slowly
body: <pre><code>df.write.partitionBy("par").format("orc").saveAsTable("mytable")
  </code></pre>
  
  <p>hello everybody , when i save a spark dataframe as a partitioned hive table, the process is very very slow, does anybody know why? Are there any parameters which should be tuned? </p>