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https://issues.apache.org/jira/browse/HDFS-6757?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14080159#comment-14080159
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Colin Patrick McCabe commented on HDFS-6757:
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bq. [~jingzhao] wrote: With INode features we now no longer have INode
replacement (exception for INodeReference which is out of picture in this
jira), thus I think it's fine to use INode in the lease map. However, in the
meanwhile, I'm not sure if this will increase the possibility of memory leak
due to failing to update the lease map (maybe because of buggy code).
I agree-- we might get some really nasty bugs by having a bunch of references
to inodes that somehow are "really" deleted here. It would only require a
minor mistake in the code. The memory savings doesn't seem worth it (and, of
course, we're already reducing memory consumption by switching away from
strings)
bq. [~daryn] wrote: However, isn't a bug if there's no lease during a close op?
Perhaps removeLeases skips missing leases and calls a removeLease that requires
a lease, and the close edit op calls removeLease?
Imagine that a client gets SIGSTOP, and then its hard lease on its
open-for-write file expires and is removed. The client can be resumed later,
come back and then try to close. So not being able to find a lease during a
close is certainly worthy of a nasty log message, but I don't think we can call
it a bug.
[~wheat9]: I apologize if it is a dumb question, but do we need to pass
removedUCFiles around everywhere? Can't we just look at the inodes in the
lists we're passing and see if they're under construction? [~jingzhao]'s made
a good point about how we don't want to remove leases for open files just
because we deleted an under-construction inode inside a snapshot. But we
should be able to tell whether or not we're not removing the "current" version
of the UC inode somehow, right?
> Simplify lease manager with INodeID
> -----------------------------------
>
> Key: HDFS-6757
> URL: https://issues.apache.org/jira/browse/HDFS-6757
> Project: Hadoop HDFS
> Issue Type: Improvement
> Reporter: Haohui Mai
> Assignee: Haohui Mai
> Attachments: HDFS-6757.000.patch, HDFS-6757.001.patch,
> HDFS-6757.002.patch, HDFS-6757.003.patch, HDFS-6757.004.patch
>
>
> Currently the lease manager records leases based on path instead of inode
> ids. Therefore, the lease manager needs to carefully keep track of the path
> of active leases during renames and deletes. This can be a non-trivial task.
> This jira proposes to simplify the logic by tracking leases using inodeids
> instead of paths.
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