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https://issues.apache.org/jira/browse/CASSANDRA-12937?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17834286#comment-17834286
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Stefan Miklosovic commented on CASSANDRA-12937:
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The reason the above is happening has something to do with how TCM works. When
we shut down a node and we restart it, TCM will basically reconstruct all
schema from scratch by replying its log, one schema change after another, so by
definition when we apply all transformations, we will get the final schema.
With the current state of the patch I opened, when we start a node for the
first time, the patch will resolve the default compressor from cassandra.yaml
and it will use that one. However, upon restart, with changed default, TCM will
replay it all over again, but now with the changed default so it will not match
anymore.
Honestly, I am not sure how to fix this. This problem also occurs in the branch
of Claude without my commits too and the test fails there as well. I think that
this patch was so long time around that TCM was introduced and it does not play
together anymore.
> Default setting (yaml) for SSTable compression
> ----------------------------------------------
>
> Key: CASSANDRA-12937
> URL: https://issues.apache.org/jira/browse/CASSANDRA-12937
> Project: Cassandra
> Issue Type: Improvement
> Components: Local/Config
> Reporter: Michael Semb Wever
> Assignee: Stefan Miklosovic
> Priority: Low
> Labels: AdventCalendar2021
> Fix For: 5.x
>
> Time Spent: 8h
> Remaining Estimate: 0h
>
> In many situations the choice of compression for sstables is more relevant to
> the disks attached than to the schema and data.
> This issue is to add to cassandra.yaml a default value for sstable
> compression that new tables will inherit (instead of the defaults found in
> {{CompressionParams.DEFAULT}}.
> Examples where this can be relevant are filesystems that do on-the-fly
> compression (btrfs, zfs) or specific disk configurations or even specific C*
> versions (see CASSANDRA-10995 ).
> +Additional information for newcomers+
> Some new fields need to be added to {{cassandra.yaml}} to allow specifying
> the field required for defining the default compression parameters. In
> {{DatabaseDescriptor}} a new {{CompressionParams}} field should be added for
> the default compression. This field should be initialized in
> {{DatabaseDescriptor.applySimpleConfig()}}. At the different places where
> {{CompressionParams.DEFAULT}} was used the code should call
> {{DatabaseDescriptor#getDefaultCompressionParams}} that should return some
> copy of configured {{CompressionParams}}.
> Some unit test using {{OverrideConfigurationLoader}} should be used to test
> that the table schema use the new default when a new table is created (see
> CreateTest for some example).
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