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https://issues.apache.org/jira/browse/HADOOP-12667?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15068449#comment-15068449
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Chris Nauroth commented on HADOOP-12667:
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If the goal is to support HBase's WAL management, then another aspect is that
HBase expects atomicity from this call. Atomicity would guarantee that for 2
concurrent threads/processes calling {{createNonRecursive}}, one of the callers
succeeds and the other fails. HBASE-11045 has some great discussion of the
expected semantics, especially this comment:
https://issues.apache.org/jira/browse/HBASE-11045?focusedCommentId=13977198&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-13977198
This means that an implementation that just checks for existence before
allowing the create to proceed is insufficient. There would be a race
condition allowing 2 concurrent callers to think the path exists and proceed
with their creates.
In hadoop-azure, this problem is solved by making concurrent callers acquire a
mutually exclusive lease on the blob before doing the create. Blob leases are
a feature of Azure Storage. I'm not aware of any lease functionality like this
available in S3.
> s3a: Support createNonRecursive API
> -----------------------------------
>
> Key: HADOOP-12667
> URL: https://issues.apache.org/jira/browse/HADOOP-12667
> Project: Hadoop Common
> Issue Type: Bug
> Components: fs/s3
> Reporter: Sean Mackrory
> Assignee: Sean Mackrory
> Attachments: HADOOP-12667.001.patch
>
>
> HBase and other clients rely on the createNonRecursive API, which was
> recently un-deprecated. S3A currently does not support it.
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