Currently, the system.compaction_history table miss precious
information like the type of compaction (cleanup, major, resharding,
etc) or the sstable generations involved (in and out) used countless
times to diagnose issues.
Thus, the commit extend the current definition of the table by adding
the following columns:
+ "compaction_type" (text)
+ "started_at" (int)
+ "shard_id" (int)
+ "sstables_in" (list<sstableinfo_type>)
+ "sstables_out" (list<sstableinfo_type>)
+ "total_tombstone_purge_attempt" (long)
+ "total_tombstone_purge_failure_due_to_overlapping_with_memtable" (long)
+ "total_tombstone_purge_failure_due_to_overlapping_with_uncompacting_sstable" (long)
Furthermore, the commit introduces a new feature flag in order to
prevent nodes from writing data to new columns when a cluster is
not fully upgraded.
