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Ryan King commented on CASSANDRA-981: ------------------------------------- >I think what we want to do is have the "dynamic" part just apply to >endpoint-sorting, and leave replica determination up to the strategy in terms >of DC + Rack. I think this could be good for more than network distance, it would also help a cluster route around a node that is slow (either permanently or temporarily). In addition to being in compaction, a node that has just been restarted and therefore has empty caches should be routed around (but not completely, since it needs traffic in order to warm its caches). > Dynamic endpoint snitch > ----------------------- > > Key: CASSANDRA-981 > URL: https://issues.apache.org/jira/browse/CASSANDRA-981 > Project: Cassandra > Issue Type: New Feature > Components: Core > Reporter: Jonathan Ellis > Fix For: 0.7 > > > An endpoint snitch that automatically and dynamically infers "distance" to > other machines without having to explicitly configure rack and datacenter > positions solves two problems: > The killer feature here is adapting to things like compaction or a > failing-but-not-yet-dead disk. This is important, since when we are doing > reads we pick the "closest" replica for actually reading data from (and only > read md5s from other replicas). This means that if the closest replica by > network topology is temporarily slow due to compaction (for instance), we'll > have to block for its reply even if we get the other replies much much faster. > Not having to manually re-sync your configuration with your network topology > when changes (adding machines) are made is a nice bonus. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.