database administration - When should I run cleanup in Cassandra? -


cassandra nodetool has command called cleanup:

cleanup [keyspace][cf_name]

triggers immediate cleanup of keys no longer belonging node. has same effect on node major compaction in terms of temporary increase in disk space usage , increase in disk i/o. optionally takes list of column family names.

my questions are:

  1. when node having keys not belonging it?
  2. when should issue cleanup?
  3. should cleanup regularly (e.g. once per week)?

when node having keys not belonging it?

when have added new nodes cluster, decreased replication factor or moved tokens.

when should issue cleanup?

after 1 of above operations, if need save disk space. there no harm in delaying running - there performance impact , reason save disk space.

should cleanup regularly (e.g. once per week)?

no, if need save space after 1 of above operations.


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