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https://issues.apache.org/jira/browse/CASSANDRA-10496?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15384776#comment-15384776
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Wei Deng commented on CASSANDRA-10496:
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A lot of things have changed in the last couple of months. Now that TWCS is the
official compaction strategy for time-series data going forward (and DTCS going
obsolete), shall we update the title of this JIRA to "Make TWCS split
partitions based on time during compaction" and revisit the priority of this
JIRA? I'm sure we might want to review a few other outstanding enhancement
JIRAs that were originally intended for DTCS as well.
> Make DTCS split partitions based on time during compaction
> ----------------------------------------------------------
>
> Key: CASSANDRA-10496
> URL: https://issues.apache.org/jira/browse/CASSANDRA-10496
> Project: Cassandra
> Issue Type: Improvement
> Reporter: Marcus Eriksson
> Labels: dtcs
> Fix For: 3.x
>
>
> To avoid getting old data in new time windows with DTCS (or related, like
> [TWCS|CASSANDRA-9666]), we need to split out old data into its own sstable
> during compaction.
> My initial idea is to just create two sstables, when we create the compaction
> task we state the start and end times for the window, and any data older than
> the window will be put in its own sstable.
> By creating a single sstable with old data, we will incrementally get the
> windows correct - say we have an sstable with these timestamps:
> {{[100, 99, 98, 97, 75, 50, 10]}}
> and we are compacting in window {{[100, 80]}} - we would create two sstables:
> {{[100, 99, 98, 97]}}, {{[75, 50, 10]}}, and the first window is now
> 'correct'. The next compaction would compact in window {{[80, 60]}} and
> create sstables {{[75]}}, {{[50, 10]}} etc.
> We will probably also want to base the windows on the newest data in the
> sstables so that we actually have older data than the window.
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