title: Factors that limit speed Presto?
body: <p>I have just installed Presto today on our server at work (version 0.57) and when doing a select count(*) from log; it takes more than 17 minutes for a table with only 640 million records (~64GB).</p>
  
  <p>Now I am under the impression that this is way too slow for presto, but I am not sure.</p>
  
  <p>Some info:</p>
  
  <p>Hive and Presto have both been installed with default configurations from their documentation.</p>
  
  <p>Hive table is an external table with about 24 columns most of them String and 3 of them are Array and the file is stored as Textfile (Hive complains about RCFile with my file for some reason).</p>
  
  <p>The table will be mostly used for grouping and count operations.</p>
  
  <p>Do you have any tips for increasing performance or what the targetted query time should be for a simple count(*) of a table?</p>
  
  <p>Cheers</p>