[Hadoop-common-dev] [jira] Created: (HADOOP-4696) Better handling of dfsadmin command when namenode is slow

Better handling of dfsadmin command when namenode is slow
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Key: HADOOP-4696
URL: https://issues.apache.org/jira/browse/HADOOP-4696
Project: Hadoop Core
Issue Type: New Feature
Components: dfs
Affects Versions: 0.18.2
Reporter: Koji Noguchi


Probably when hitting HADOOP-3810, Namenode became unresponsive. Large time spent in GC.
All dfs/dfsadmin command were timing out.

WebUI was coming up after waiting for a long time.

Maybe setting a long timeout would have made the dfsadmin command go through.
But it would be nice to have a separate queue/handler which doesn't compete with regular rpc calls.

All I wanted to do was dfsadmin -safemode enter, dfsadmin -finalizeUpgrade ...