We have a CHD 5.8.3 cluster, each node has hdfs, yarn and Impalad processes.
We saw that we have red alerts on the Impala service on swap issues,
We did all the calculation with OS, YARN and HDFS process memory allocation per server so there will not be memory over allocation.
After it, we've found that Impala has JVM heap memory except for mem_limit so we set the max heap to 8G so it will be controlled (and remove 8G from the other components on the node).
But now we still see swap issues on Impala and other Hadoop services and our consumers complain about slowness and out of memory on Impala queries
Can you help us to figure why we have red alerts on Impala service in the Cloudera manager? What other reason can be for this?