Yiqun Lin created HDFS-11398:
--------------------------------
Summary:
TestDataNodeVolumeFailure#testUnderReplicationAfterVolFailure still fails
intermittently
Key: HDFS-11398
URL: https://issues.apache.org/jira/browse/HDFS-11398
Project: Hadoop HDFS
Issue Type: Bug
Affects Versions: 3.0.0-alpha2
Reporter: Yiqun Lin
Assignee: Yiqun Lin
The test {{TestDataNodeVolumeFailure#testUnderReplicationAfterVolFailure}}
still fails intermittently in trunk after HDFS-11316. The stack infos:
{code}
java.util.concurrent.TimeoutException: Timed out waiting for DN to die
at
org.apache.hadoop.hdfs.DFSTestUtil.waitForDatanodeDeath(DFSTestUtil.java:702)
at
org.apache.hadoop.hdfs.server.datanode.TestDataNodeVolumeFailureReporting.testSuccessiveVolumeFailures(TestDataNodeVolumeFailureReporting.java:218
{code}
I looked into this and found there is one chance that the vaule
{{UnderReplicatedBlocksCount}} will be no longer > 0. The following is my
analysation:
In test {{TestDataNodeVolumeFailure.testUnderReplicationAfterVolFailure}}, it
uses creating file to trigger the disk error checking. The related codes:
{code}
Path file1 = new Path("/test1");
DFSTestUtil.createFile(fs, file1, 1024, (short)3, 1L);
DFSTestUtil.waitReplication(fs, file1, (short)3);
// Fail the first volume on both datanodes
File dn1Vol1 = new File(dataDir, "data"+(2*0+1));
File dn2Vol1 = new File(dataDir, "data"+(2*1+1));
DataNodeTestUtils.injectDataDirFailure(dn1Vol1, dn2Vol1);
Path file2 = new Path("/test2");
DFSTestUtil.createFile(fs, file2, 1024, (short)3, 1L);
DFSTestUtil.waitReplication(fs, file2, (short)3);
{code}
This will lead one problem: If the cluster is busy, and it coats so long time
to wait replication of file2 to be desired value. And there is one chance that
the under replication blocks of file1 can also be replication in cluster. If
this is done, the condition {{underReplicatedBlocks > 0}} will be never
satisfied.
And this can be reproduced in my local env.
Actually, we can use a easy way {{DataNodeTestUtils.waitForDiskError}} to
replace this, it runs fast and be more reliable.
--
This message was sent by Atlassian JIRA
(v6.3.15#6346)
---------------------------------------------------------------------
To unsubscribe, e-mail: hdfs-dev-unsubscr...@hadoop.apache.org
For additional commands, e-mail: hdfs-dev-h...@hadoop.apache.org
