Hi Dominik, an Oak cluster on MongoDB does not provide strong consistency guarantees. The same is actually true for all DocumentNodeStore cluster setups, independent of the DocumentStore backend. A write on one cluster node will not be visible immediately on other cluster nodes. The change will eventually show up, but depends on the timing of background operations running. There are existing tests like ClusterTest [0], which check this behaviour.
If you still think changes are not properly propagated through the cluster, then please create a test in oak-core using existing utilities. Oak currently does not start up its own MongoDB during tests, but rather depends on a running instance. Regards Marcel [0] https://github.com/apache/jackrabbit-oak/blob/jackrabbit-oak-1.4.0/oak-core /src/test/java/org/apache/jackrabbit/oak/plugins/document/ClusterTest.java On 08/03/16 17:22, "Dominik Förderreuther" wrote: >Hi, > >we have merge conflicts in our cluster environment. I could reproduce [1, >2] merge conflicts in an integration test with an embedded MongoDB and >two clustered repositories. I have already created a pull request [3] for >the test-module. Would be great if you could give me some comments >regarding the sense of meaning of my test setup and the experienced >exception. > >At the moment, I assume there is a problem with the write lock within >org.apache.jackrabbit.oak.spi.state.AbstractNodeStoreBranch.BranchState#me >rge and concurrent cluster replication activity, but I¹m not done with >debugging. I¹ll also merge the integration test into trunk within the >next days. > >Thanks and best regards, >Dominik > >[1] Repository: >https://github.com/dfoerderreuther/jackrabbit-oak/<https://github.com/dfoe >rderreuther/jackrabbit-oak/tree/1.0/oak-it/cluster> respectively: >https://github.com/dfoerderreuther/jackrabbit-oak/tree/1.0/oak-it/cluster >[2] Example Test-Report: >https://github.com/dfoerderreuther/jackrabbit-oak/blob/1.0/oak-it/cluster/ >reports/2REPOS_50THREADS.md >[3] Pull-Request: https://github.com/apache/jackrabbit-oak/pull/51 > > > >-- > >Dominik Förderreuther | Senior Consultant | Adobe Systems GmbH | >+49.89.31705.488 (office) | +49.172.8082132 (mobile) | [email protected]
