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  1. Cassandra
  2. CASSANDRA-15696

Only track ideal CL failure when request CL is met

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      When ideal_consistency_level is set (CASSANDRA-13289), we currently increment a counter if a request doesn’t meet the consistency level specified in the configuration (or through JMX).

      At the moment, we increment the counter if the query was successful or not. I think it would be slightly better if we only incremented the counter if the ideal CL wasn’t achieved but the query’s CL was met.

      The original JIRA, stated the following as an objective:

      If your application writes at LOCAL_QUORUM how often are those writes failing to achieve EACH_QUORUM at other data centers. If you failed your application over to one of those data centers roughly how inconsistent might it be given the number of writes that didn't propagate since the last incremental repair?

      The main benefit to the JIRA was to set a CL higher than the CL being used, and to track how often we weren’t able to hit that CL despise hitting the underlying CL. We should only increment the counter in a case where we were able to meet the query provided consistency but were unable to meet the ideal consistency level.

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              rustyrazorblade Jon Haddad
              rustyrazorblade Jon Haddad
              Jon Haddad
              Dinesh Joshi
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