[
https://issues.apache.org/jira/browse/HDFS-3979?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Lars Hofhansl updated HDFS-3979:
--------------------------------
Attachment: hdfs-3979-v3.txt
This little change makes TestHSync fail most of the time - without the rest of
the patch, and never with this patch.
(In HDFS-744 I had avoided this race, by updating the sync metric first. I know
that was a hack... By updating the metric last in BlockReceiver.flushOrSync,
this race becomes apparent again).
We do have pipeline tests that seem to verify correct pipeline behavior in the
face of failures via fault injection: TestFiPipelines and TestFiHFlush.
In terms of the API3/API4 discussion, I think we agree that hflush should
follow API4, right? (otherwise we'd have unduly complex code)
> Fix hsync and hflush semantics.
> -------------------------------
>
> Key: HDFS-3979
> URL: https://issues.apache.org/jira/browse/HDFS-3979
> Project: Hadoop HDFS
> Issue Type: Bug
> Components: data-node, hdfs client
> Affects Versions: 0.22.0, 0.23.0, 2.0.0-alpha
> Reporter: Lars Hofhansl
> Assignee: Lars Hofhansl
> Attachments: hdfs-3979-sketch.txt, hdfs-3979-v2.txt, hdfs-3979-v3.txt
>
>
> See discussion in HDFS-744. The actual sync/flush operation in BlockReceiver
> is not on a synchronous path from the DFSClient, hence it is possible that a
> DN loses data that it has already acknowledged as persisted to a client.
> Edit: Spelling.
--
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
