liutongwei created HDFS-16490:
---------------------------------
Summary: CoordinatedCall to observer namnode will requeue util the
active namenode logsync success
Key: HDFS-16490
URL: https://issues.apache.org/jira/browse/HDFS-16490
Project: Hadoop HDFS
Issue Type: Improvement
Components: namanode
Reporter: liutongwei
As observer namenode is serving CoordinatedCall, it will requeue call if server
stateId smaller than client stateId. In a heavy read but rare write cluster,
the client may get a stateId not replicated to journal node.
For example, when client call FSNamesystem.getBlockLocations and need
updateAccessTime , active namenode call getEditLog().logTimes() but not
logSync(). Then client get a stateId which do not replicated to journal node.
So observer name will requeue the client call when nothing trigger a logSync().
In rare write cluster, this elapsed time could be from seconds to minutes.
For fix this, we could add a requeue call timeout config or return client
stateId with active committed txid.
--
This message was sent by Atlassian Jira
(v8.20.1#820001)
---------------------------------------------------------------------
To unsubscribe, e-mail: hdfs-dev-unsubscr...@hadoop.apache.org
For additional commands, e-mail: hdfs-dev-h...@hadoop.apache.org
