To find the top 10 counts , which is better using top(10) with Ordering on the value, or swapping the key value and ordering on the key ? For example which is better below ? Or does it matter
val top10 = logs.filter(log => log.responseCode != 200).map(log => (log.endpoint, 1)).reduceByKey(_ + _).top(10)(Ordering[Long].on(x=>x._2)) val top10 = logs.filter(log => log.responseCode != 200).map(log => (log.endpoint, 1)).reduceByKey((x,y)=>x+y).map(x=>(x._2,x._1)).sortByKey(false).take(10) val top10 = logs.filter(log => log.responseCode != 200).map(log => (log.endpoint, 1)).reduceByKey((x,y)=>x+y).map(pair => pair.swap).top(10)
