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Jeff Jirsa commented on CASSANDRA-10280:
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[~jshook] I would expect it not to affect tombstone compaction scheduling,
based on my reading and familiarity with the code.
Now for ponies/bikeshed:
I want to - respectfully and humbly - suggest that IF we're breaking backwards
compatibility (and I'll state that I believe it's necessary to kill
{{max_sstable_age_days}} for DTCS to be viable in the real world), that
CASSANDRA-9666 accomplishes this same basic behavior in a very similar manner
in a much more predictable and easier-to-operate manner, without the weird
arithmetic of the Target class.
I realize that wholesale swapping of strategies is not easy, but we're already
breaking backward compatibility here. This patch combined with CASSANDRA-10276
certainly fix a lot of problems with DTCS, so I'm in favor of them (as a heavy
user of DTCS), but I'm still convinced that 9666 is more predictable and easier
to reason about than DTCS+10280+10276
> Make DTCS work well with old data
> ---------------------------------
>
> Key: CASSANDRA-10280
> URL: https://issues.apache.org/jira/browse/CASSANDRA-10280
> Project: Cassandra
> Issue Type: Sub-task
> Components: Core
> Reporter: Marcus Eriksson
> Assignee: Marcus Eriksson
> Fix For: 3.x, 2.1.x, 2.2.x
>
>
> Operational tasks become incredibly expensive if you keep around a long
> timespan of data with DTCS - with default settings and 1 year of data, the
> oldest window covers about 180 days. Bootstrapping a node with vnodes with
> this data layout will force cassandra to compact very many sstables in this
> window.
> We should probably put a cap on how big the biggest windows can get. We could
> probably default this to something sane based on max_sstable_age (ie, say we
> can reasonably handle 1000 sstables per node, then we can calculate how big
> the windows should be to allow that)
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