My cluster have 4 datanode. Each Datanode has 32G RAM.
Recently, the Datanode has been reported Exception Out Of Memory.
I looed up some document, just mentioned namenode memory situations.
CDH Manager，Host memory usage chart display physical memory is full, but The role of resident memory less than 1G.
i don't know why it took so much of physical memory.
I have turn off all other services,just run the hdfs service.