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https://issues.apache.org/jira/browse/CASSANDRA-6106?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13779586#comment-13779586
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Rick Branson commented on CASSANDRA-6106:
-----------------------------------------
Yeah you're right. The thread will probably occasionally get interrupted by the
kernel between the currentTimeMillis() and the nanoTime() call. It'd probably
take a bunch of iterations to properly "calibrate" the base clock. This is
getting pretty far into the extremely-fragile territory.
> QueryState.getTimestamp() & FBUtilities.timestampMicros() reads current
> timestamp with System.currentTimeMillis() * 1000 instead of System.nanoTime()
> / 1000
> ------------------------------------------------------------------------------------------------------------------------------------------------------------
>
> Key: CASSANDRA-6106
> URL: https://issues.apache.org/jira/browse/CASSANDRA-6106
> Project: Cassandra
> Issue Type: Bug
> Components: Core
> Environment: DSE Cassandra 3.1, but also HEAD
> Reporter: Christopher Smith
> Priority: Minor
> Labels: collision, conflict, timestamp
> Attachments: microtimstamp.patch
>
>
> I noticed this blog post: http://aphyr.com/posts/294-call-me-maybe-cassandra
> mentioned issues with millisecond rounding in timestamps and was able to
> reproduce the issue. If I specify a timestamp in a mutating query, I get
> microsecond precision, but if I don't, I get timestamps rounded to the
> nearest millisecond, at least for my first query on a given connection, which
> substantially increases the possibilities of collision.
> I believe I found the offending code, though I am by no means sure this is
> comprehensive. I think we probably need a fairly comprehensive replacement of
> all uses of System.currentTimeMillis() with System.nanoTime().
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