title: Can two executors / drivers from different Spark applications run on same node in cluster mode?
body: <p>I read an article in Medium which claims that the number of executors + 1 (for driver), should be a multiple of 3, to efficiently utilize the core on a machine (16 cores, in this case, i.e, 5 per executor and 1 will be reserved for OS and node manager)</p>
  <p>I am unable to validate this statement using experimenting on the cluster due to practical reasons. Did anybody try this? or have reference to code/documentation stating Yarn nodes will/not share cluster resources between another Spark application?</p>