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YARN Forum

Yarn Containers Not Using Ram

  • #49071
    Aaron Zimmerman

    The worker nodes on my cluster won’t use more than 11 of the 30 total (24 allocated) for mapreduce jobs running in Yarn, I’m hoping someone could help me figure out why.

    I followed the steps listed here:, and to set various memory parameters, but no matter what I try, the nodes on the cluster don’t use more than 11GB of the allocated 26GB.

    The yarn resource manager reports that it is using all of the allocated memory in the status across the top, but according to TOP and other such, it is not.

    Using ps, I see org.apache.hadoop.mapred.YarnChild processes being created with -Xmx756m, but I can’t find this anywhere in mapreduce or yarn configurations. Does anyone have an idea what might be constraining the usage of Ram?

    yarn.nodemanager.resource.memory-mb = 24576
    yarn.scheduler.minimum-allocation-mb = 3072
    yarn_heapsize=20000 (not really clear to me what this does…?)

    mapreduce2 config: = 4096
    mapreduce.reduce.memory.mb = 8192 = -Xmx3500 = -Xmx7000


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