title: spark.sql.hive.filesourcePartitionFileCacheSize
body: <p>Just wonder if anyone is aware of this warning info</p>
  
  <pre><code>18/01/10 19:52:56 WARN SharedInMemoryCache: Evicting cached table partition metadata from memory due to size constraints
  (spark.sql.hive.filesourcePartitionFileCacheSize = 262144000 bytes). This may impact query planning performance
  </code></pre>
  
  <p>I've seen this a lot when trying to load some big dataframe with many partitions from S3 into spark.</p>
  
  <p>It never really causes any issues to the job, just wonder what is the use of that config property and how to tune it properly.</p>
  
  <p>Thanks</p>