11 Replies Latest reply on Jan 10, 2011 6:56 AM by Manik Surtani

    Lack of 'Virtual node' in infinispan consistent hash?

    Changgeng Li Newbie



      In our test with infinispan 4.2.0.Final, we found that the data on the cluster is a very non-uniform distribution. With 14 entries in a 6 nodes cluster, one node got 11 entries, 3 nodes got one each, and the other two nodes got node.


      I read the code of AbstractWheelConsistentHash, it seems infinispan doesn't using the virtual node idea, that when adding a new node, it will be mapped to several virtual nodes to achieve a better distribution. I think the following log entry can show this.


      2011-01-04 06:22:07,165 TRACE [org.infinispan.distribution.ch.AbstractWheelConsistentHash](OOB-19,ana,perf-srm6-57520) Position are: {29=perf-srm4-51743, 1664=perf-srm3-10713, 2063=perf-srm-45067, 2594=perf-srm6-57520, 4055=perf-srm2-58295, 4477=perf-srm5-54}


      Could the developer confirm if that is true and provide any resolution to gain a better distribution?


      Thank you.