标签:local wan app oca highlight string void ext master
package com.wll; import org.apache.spark.SparkConf; import org.apache.spark.api.java.JavaRDD; import org.apache.spark.api.java.JavaSparkContext; public class Persist { static SparkConf conf=new SparkConf().setMaster("local").setAppName("persist"); static JavaSparkContext sc=new JavaSparkContext(conf); public static void main(String[] args){ noCache(); //cache(); } public static void noCache(){ JavaRDD<String> list=sc.textFile("C:\\Users\\wanglonglong\\Desktop\\hive-default.xml"); long beginTime=System.currentTimeMillis(); long count=list.count(); System.out.println("无持久化第一次"+(System.currentTimeMillis()-beginTime)); beginTime=System.currentTimeMillis(); count=list.count(); System.out.println("无持久化第二次"+(System.currentTimeMillis()-beginTime)); } public static void cache(){ JavaRDD<String> list=sc.textFile("C:\\Users\\wanglonglong\\Desktop\\hive-default.xml").cache(); long beginTime=System.currentTimeMillis(); long count=list.count(); System.out.println("持久化第一次"+(System.currentTimeMillis()-beginTime)); beginTime=System.currentTimeMillis(); count=list.count(); System.out.println("持久化第二次"+(System.currentTimeMillis()-beginTime)); } }
标签:local wan app oca highlight string void ext master
原文地址:https://www.cnblogs.com/wakerwang/p/9568440.html