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https://issues.apache.org/jira/browse/CASSANDRA-9627?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14595132#comment-14595132
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Benedict commented on CASSANDRA-9627:
-------------------------------------
If that's the case, I'm reasonably happy to reduce the priority and change the
scope of the ticket.
[~JoshuaMckenzie]: Could you confirm before I do this that we're certain an
fsync of the file creates a happens-before relation for all directory
modifications that have come before? If repairing the directory results in any
slip backwards or forwards in time of a modification to the structure, we could
be SOL.
I'm particularly thinking of this in relation to CASSANDRA-7066, where we'll be
relying on the (non-)\?presence of files to ensure transactional swapping of
our live sstable contents. The risk exists with or without CASSANDRA-7066, but
it will widen our surface of exposure pretty significantly if we're wrong,
since we will in rapid succession make a number of directory modifications that
all require a happens-before guarantee.
> fsync should not be "best effort" (and silently fail on e.g. windows)
> ---------------------------------------------------------------------
>
> Key: CASSANDRA-9627
> URL: https://issues.apache.org/jira/browse/CASSANDRA-9627
> Project: Cassandra
> Issue Type: Bug
> Components: Core
> Reporter: Benedict
> Priority: Blocker
> Fix For: 2.2.0 rc2
>
>
> Currently we make an effort to synchronize both the file contents and the
> directory contents. Both are essential to ensure no data loss. Currently we
> just try to do this, and ignore the problem if we can't. Presumably this
> behaviour was to "sort of" support Windows (i.e. not crash). Now we
> officially support Windows, we need to behave better, and really IMO we
> should _never_ for any platform ignore a failure here. It should be part of
> our pre-flight checks: if we cannot do it, we cannot run safely.
> It looks like this may be supported trivially through FileChannel, by opening
> one on the directory itself (and calling force()), although it's not clear if
> this will still be supported in Java 9 [see discussion
> here|http://mail.openjdk.java.net/pipermail/nio-dev/2015-May/003140.html].
> [~JoshuaMcKenzie]: assigning to you for now, just so it's tracked by the
> Windows overlord.
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