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https://issues.apache.org/jira/browse/CASSANDRA-9669?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14745432#comment-14745432
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Benedict commented on CASSANDRA-9669:
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bq. Memtable.isCleanAfter doesn't look right.
Good catch, I have inverted the implementation and meaning, and renamed it to
{{mayContainDataSince}}
bq. "ka" reader says compatible with "kb" data but read will fail
Hmm. This is a bit of a problem. I must admit I didn't look too closely at
compatibility, since I assumed the whole point of the major/minor chars was to
permit intra- and extra-version sstable version increments. Without that, this
seems to be a bit of a mess. I guess we will need to increment all of the
sstable versions past the max of the current. We should perhaps rethink
accepting all versions <= first char of current, as it doesn't permit much
flexibility.
Thanks. I'll address this, your nits, and what looks like a relatively
innocuous problem with DTCS shortly.
> If sstable flushes complete out of order, on restart we can fail to replay
> necessary commit log records
> -------------------------------------------------------------------------------------------------------
>
> Key: CASSANDRA-9669
> URL: https://issues.apache.org/jira/browse/CASSANDRA-9669
> Project: Cassandra
> Issue Type: Bug
> Components: Core
> Reporter: Benedict
> Assignee: Benedict
> Priority: Critical
> Labels: correctness
> Fix For: 3.x, 2.1.x, 2.2.x, 3.0.x
>
>
> While {{postFlushExecutor}} ensures it never expires CL entries out-of-order,
> on restart we simply take the maximum replay position of any sstable on disk,
> and ignore anything prior.
> It is quite possible for there to be two flushes triggered for a given table,
> and for the second to finish first by virtue of containing a much smaller
> quantity of live data (or perhaps the disk is just under less pressure). If
> we crash before the first sstable has been written, then on restart the data
> it would have represented will disappear, since we will not replay the CL
> records.
> This looks to be a bug present since time immemorial, and also seems pretty
> serious.
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