Deploy MapReduce Client Plugin & Configurations

Deploy MapReduce Client Plugin

1. Add client jar to the classpath of each NodeManager, e.g., /share/hadoop/mapreduce/

The jar for MapReduce is located in <RSS_HOME>/jars/client/mr/rss-client-mr-XXXXX-shaded.jar

2. Update MapReduce conf to enable Uniffle, e.g.

   -Dmapreduce.rss.coordinator.quorum=<coordinatorIp1>:19999,<coordinatorIp2>:19999
   -Dyarn.app.mapreduce.am.command-opts=org.apache.hadoop.mapreduce.v2.app.RssMRAppMaster
   -Dmapreduce.job.map.output.collector.class=org.apache.hadoop.mapred.RssMapOutputCollector
   -Dmapreduce.job.reduce.shuffle.consumer.plugin.class=org.apache.hadoop.mapreduce.task.reduce.RssShuffle
   

Note that the RssMRAppMaster will automatically disable slow start (i.e., mapreduce.job.reduce.slowstart.completedmaps=1) and job recovery (i.e., yarn.app.mapreduce.am.job.recovery.enable=false)

MapReduce Specific Configurations

Property Name	Default	Description
mapreduce.rss.client.max.buffer.size	3k	The max buffer size in map side
mapreduce.rss.client.batch.trigger.num	50	The max batch of buffers to send data in map side

Remote Spill (Experimental)

In cloud environment, VM may have very limited disk space and performance. This experimental feature allows to reduce tasks to spill data to remote storage (e.g., hdfs)

Property Name	Default	Description
mapreduce.rss.reduce.remote.spill.enable	false	Whether to use remote spill
mapreduce.rss.reduce.remote.spill.attempt.inc	1	Increase reduce attempts as Hadoop FS may be easier to crash than disk
mapreduce.rss.reduce.remote.spill.replication	1	The replication number to spill data to Hadoop FS
mapreduce.rss.reduce.remote.spill.retries	5	The retry number to spill data to Hadoop FS

Notice: this feature requires the MEMORY_LOCALFILE_HDFS storage type mode.