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  1. Cassandra
  2. CASSANDRA-9830

Option to disable bloom filter in highest level of LCS sstables

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      We expect about 90% of data to be in the highest level of LCS in a fully populated series. (See also CASSANDRA-9829.)

      Thus if the user is primarily asking for data (partitions) that has actually been inserted, the bloom filter on the highest level only helps reject sstables about 10% of the time.

      We should add an option that suppresses bloom filter creation on top-level sstables. This will dramatically reduce memory usage for LCS and may even improve performance as we no longer check a low-value filter.

      (This is also an idea from RocksDB.)

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              • Assignee:
                pauloricardomg Paulo Motta (Deprecated)
                Reporter:
                jbellis Jonathan Ellis
                Authors:
                Paulo Motta (Deprecated)
                Reviewers:
                Carl Yeksigian
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                  Updated:
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