Todd Lipcon created HDFS-3955:
---------------------------------
Summary: QJM: Make acceptRecovery() atomic
Key: HDFS-3955
URL: https://issues.apache.org/jira/browse/HDFS-3955
Project: Hadoop HDFS
Issue Type: Sub-task
Components: ha
Affects Versions: QuorumJournalManager (HDFS-3077)
Reporter: Todd Lipcon
Assignee: Todd Lipcon
Per one of the TODOs in Journal.java, there is currently a lack of atomicity in
the {{acceptRecovery()}} code path. In particular, we have the following
actions executed non-atomically:
- Download a new edits_inprogress_N from some other node
- Persist the paxos recovery file to disk.
If the JN crashes between these two steps, then we may be left in the state
whereby the edits_inprogress file has different data than the Paxos data left
over on the disk from a previous recovery attempt. This causes the next
{{prepareRecovery()}} to fail with an AssertionError.
I discovered this by randomly injecting a fault between the two steps, and then
running the randomized fault test on a cluster. This resulted in some
AssertionErrors in the test logs.
--
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
