hadoop-hdfs-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Xiaobo Peng (JIRA)" <j...@apache.org>
Subject [jira] [Created] (HDFS-4222) NN is unresponsive and lose hearbeats of DNs when Hadoop is configured to use LADP and LDAP has issues
Date Thu, 22 Nov 2012 01:08:58 GMT
Xiaobo Peng created HDFS-4222:
---------------------------------

             Summary: NN is unresponsive and lose hearbeats of DNs when Hadoop is configured
to use LADP and LDAP has issues
                 Key: HDFS-4222
                 URL: https://issues.apache.org/jira/browse/HDFS-4222
             Project: Hadoop HDFS
          Issue Type: Bug
          Components: name-node
    Affects Versions: 0.23.3
            Reporter: Xiaobo Peng
            Priority: Minor


For Hadoop clusters configured to access directory information by LDAP, the FSNamesystem calls
on behave of DFS clients might hang due to LDAP issues (including LDAP access issues caused
by networking issues) while holding the single lock of FSNamesystem. That will result in the
NN unresponsive and loss of the heartbeats from DNs.

The places LDAP got accessed by FSNamesystem calls are the instantiation of FSPermissionChecker,
which could be moved out of the lock scope since the instantiation does not need the FSNamesystem
lock. After the move, a DFS client hang will not affect other threads by hogging the single
lock. This is especially helpful when we use separate RPC servers for ClientProtocol and DatanodeProtocol
since the calls for DatanodeProtocol do not need to access LDAP. So even if DFS clients hang
due to LDAP issues, the NN will still be able to process the requests (including heartbeats)
from DNs.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

Mime
View raw message