Avneesh Pandey created CASSANDRA-19345:
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             Summary: Optimize disk seek using min/max column name meta data 
when the LIMIT clause is used
                 Key: CASSANDRA-19345
                 URL: https://issues.apache.org/jira/browse/CASSANDRA-19345
             Project: Cassandra
          Issue Type: Improvement
            Reporter: Avneesh Pandey
         Attachments: Jira-Ticket.pdf

{code:java}
CREATE TABLE tracking_details (
    tracker_public_id text,
    updated_at timeuuid,
    details text,
    PRIMARY KEY (tracker_public_id, updated_at)
) WITH CLUSTERING ORDER BY (updated_at DESC){code}

__
{code:java}
INSERT INTO tracking_details  (tracker_public_id, updated_at, details) 
VALUES('trk_e0544f077f7f4140bf1b961493fa99fe', now(), '{"details":[{...1-3KB 
}]}');{code}
__
__
{code:java}
nodetool flush trackingdata tracking_details{code}
 
{code:java}
INSERT INTO tracking_details  (tracker_public_id, updated_at, details) 
VALUES('trk_e0544f077f7f4140bf1b961493fa99fe', now(), '{"details":[{...1-3KB 
}]}');

INSERT INTO tracking_details  (tracker_public_id, updated_at, details) 
VALUES('trk_e0544f077f7f4140bf1b961493fa99fe', now(), '{"details":[{...1-3KB 
}]}');{code}

__
{code:java}
nodetool flush trackingdata tracking_details{code}
 
{code:java}
Compaction is disabled- 
 {'class': 'org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy', 
'enabled': 'false', 'max_threshold': '32', 'min_threshold': '4'}{code}



_Each node is reading from both sstables - *Merged data from memtables and 2 
sstables.*_ 
_{*}{*}I thought this was fixed - 
https://issues.apache.org/jira/browse/CASSANDRA-8180_
_But somehow  C* doesn't optimizes the read path_



_Tracing attached_



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