[
https://issues.apache.org/jira/browse/CASSANDRA-8519?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Sylvain Lebresne updated CASSANDRA-8519:
----------------------------------------
Priority: Minor (was: Major)
> Mechanism to determine which nodes own which token ranges without Thrift
> ------------------------------------------------------------------------
>
> Key: CASSANDRA-8519
> URL: https://issues.apache.org/jira/browse/CASSANDRA-8519
> Project: Cassandra
> Issue Type: Improvement
> Components: Core
> Reporter: Brian Hess
> Priority: Minor
>
> Right now the only way to determine which nodes own which token ranges is via
> the Thrift interface. There is not a Java/CQL driver mechanism to determine
> this. Applications that make multiple connections to Cassandra to extract
> data in parallel need this ability so they can split the data into pieces,
> and it is reasonable to want those splits to be on token range boundaries.
> Of course, once you split this way, you would want to route those queries to
> nodes that own that token range / split, for efficiency.
> This applies for both Hadoop and Spark, but other applications, too. Hadoop
> and Spark currently use Thrift to determine this topology.
> Additionally, different replication strategies and replication factors result
> in different token range ownership, so there will have to be a different
> answer based on which keyspace is used.
> It would be useful if this data was stored in a CQL table and could be simply
> queried. A suggestion would be to add a column to the
> SYSTEM.SCHEMA_KEYSPACES table (maybe a complex Map of Host to a UDT that has
> a List of (beginRange, endRange) pairs - as an example). This table would
> need to be updated on an ALTER KEYSPACE command or on a topology change
> event. This would allow the server(s) to hold this information and the
> drivers could simply query it (as opposed to having each driver manage this
> separately).
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
