[MAPREDUCE-6105] Inconsistent configuration in property mapreduce.reduce.shuffle.merge.percent

• Type: Improvement
• Status: Resolved
• Priority: Trivial
• Resolution: Fixed
• Affects Version/s: 2.4.0, 2.4.1
• Fix Version/s: 2.8.0, 3.0.0-alpha1
• Labels: newbie
• Hadoop Flags: Reviewed
• Assignee: Ray Chiang
• Reporter: Dongwook Kwon
• Created: 24/Sep/14 05:08
• Updated: 30/Aug/16 01:19
• Resolved: 16/Mar/15 20:59

Description

Similar to MAPREDUCE-5906, In MergeManagerImpl.java, the default value of MRJobConfig.SHUFFLE_MERGE_PERCENT(mapreduce.reduce.shuffle.merge.percent) should be 0.66
According to official doc.
https://hadoop.apache.org/docs/current/hadoop-mapreduce-client/hadoop-mapreduce-client-core/mapred-default.xml

    this.mergeThreshold = (long)(this.memoryLimit * 
                          jobConf.getFloat(MRJobConfig.SHUFFLE_MERGE_PERCENT, 
                                           0.90f));