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Jeff Jirsa commented on CASSANDRA-13165: ---------------------------------------- I suspect the short version is something like this: Replica A,B,C gets CQL row 1 @ TS=1 Replica A goes offline. Replica B, C gets CQL row 2 @ TS=2 Replica A comes up, replica B goes down Replica A, C get CQL row 3 @ TS=3 Replica B comes up, replica C goes down Replica A, B get CQL row 4 @ TS=4 You do a SELECT, and you get timestamps 1,3, 4 from A, 1,2, 4 FROM B, 1,2,3 from C. If A is the coordinator, it has all of the winning timestamps for its three rows, but it doesn't know that it's missing a row. When the digest mismatch happens, it still needs to do a full data read to realize it's missing row 2. > Read repair process. > -------------------- > > Key: CASSANDRA-13165 > URL: https://issues.apache.org/jira/browse/CASSANDRA-13165 > Project: Cassandra > Issue Type: Wish > Components: Coordination > Reporter: Andrey > Priority: Minor > > Why can't we send timestamps together with digests? It will reduce > unnecessary communications between coordinator and replicas. I think the size > of messages is not that matter here, because a latency( due to network) is > way more harmful. -- This message was sent by Atlassian JIRA (v6.4.14#64029) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org