Hi All:
I have mapred.tasktracker.tasks.maximum set to 4 in our conf/hadoop-site.xml, yet I frequently see 5-6 instances of org.apache.hadoop.mapred.TaskTracker$Child running on the slave nodes. Is there another setting I need to tweak in order to dial back the number of children running? The effect of running this many children is that our boxes have extremely high load factors, and eventually mapred tasks start timing out and failing.
Note that the number of instances is for a single job. I see far more if I run multiple jobs simultaneously (something we do not typically do).
This is on Hadoop 0.15.0, upgrading is not an option at the moment.
Any help appreciate...
Thanks,
C G