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Alex Petrov commented on CASSANDRA-14821: ----------------------------------------- Just as an example, even an extremely simple three-node in-jvm dtest has revealed a bug that'd be rather hard to spot otherwise: https://issues.apache.org/jira/browse/CASSANDRA-14807 > Make it possible to run multi-node coordinator/replica tests in a single JVM > ---------------------------------------------------------------------------- > > Key: CASSANDRA-14821 > URL: https://issues.apache.org/jira/browse/CASSANDRA-14821 > Project: Cassandra > Issue Type: Test > Reporter: Alex Petrov > Assignee: Alex Petrov > Priority: Major > > Currently, dtests are complex to write, hard to modify and slow to run. The > only option to manipulate a cluster state is either to shut down nodes or run > unreliable Byteman queries. > In order to improve the situation, a new Distributed Tester is proposed. It > fires up multiple Cassandra Instances in a single JVM. It is done through > having distinct class loaders in order to work around the singleton problem > in Cassandra. In order to be able to pass some information between the nodes, > a common class loader is used that loads up java standard library and several > helper classes. Tests look a lot like CQLTester tests would usually look like. > Each Cassandra Instance, with its distinct class loader is using > serialisation and class loading mechanisms in order to run instance-local > queries and execute node state manipulation code, hooks, callbacks etc. > First version mocks out Messaging Service and simplifies schema management by > simply running schema change commands on each of the instances separately. > Internode communication is mocked by passing ByteBuffers through shared class > loader. -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org