hive job spin from oozie running very slow in mr mode

[#1]

SYMPTOM: oozie-hive job is running very slow, sometimes jobs are stuck is in final stage and was not able to complete

ROOT CAUSE:

Oozie prepares the hive-site.xml for hive action, it has the mapred parameter mapreduce.job.reduces set to 1 by default,the reason for this is oozie prepare action configuration after reading core-site.xml,hdfs-site.xml,mapred-site.xml etc.with the setting of mapreduce.job.reduces=1 the job is running with single reducer hence taking a lot of time to complete.

WORKAROUND:

set mapreduce.job.reduces to -1

RESOLUTION:

there is oozie fix https://issues.apache.org/jira/browse/OOZIE-2205 enhance actionConf which are passed to hive-action.