How to calculate the token for a ByteOrderedPartitioner

Question

I'm testing the behaviour of a Cassandra cluster with different configurations. One of them uses a ByteOrderedPartitioner to distribute the keys along the nodes.

The data model is made by fat rows, each of them with a integer (IntegerType) as key with a value from 0 to 9999. I setted a ring of 10 nodes in such way:

Address      Rack    Status    State            Owns    Token
                                                     Token(bytes[0900])
node1         Up     Normal  5.14 MB         10.00%  Token(bytes[00])
node2         Up     Normal  377.42 MB       10.00%  Token(bytes[0100])
node3         Up     Normal  373.06 MB       10.00%  Token(bytes[0200])
node4         Up     Normal  966.15 KB       10.00%  Token(bytes[0300])
node5         Up     Normal  953.4 KB        10.00%  Token(bytes[0400])
node6         Up     Normal  953.26 KB       10.00%  Token(bytes[0500])
node7         Up     Normal  944.54 KB       10.00%  Token(bytes[0600])
node8         Up     Normal  953.4 KB        10.00%  Token(bytes[0700])
node9         Up     Normal  962.42 KB       10.00%  Token(bytes[0800])
node10        Up     Normal  961.31 KB       10.00%  Token(bytes[0900])

but all the load goes on the node2 and on the node3 for replica.

Why these tokens don't work? How I should fix them?

Answer 1

First, you should run cleanup on each node to make sure you're not seeing extra data that the node is no longer responsible for, post-bootstrap.

Once that is done, you can use the getRangeKeySample JMX method to get a sample of the keys on a node. You can then adjust its token to a value that moves an appropriate amount of keys to its neighbor, if necessary.

That said: you should almost certainly be using RandomPartitioner instead, to avoid exactly this problem. I've explained in posts like this how you can use clustering within a partition key to do the kind of ordering you might otherwise be tempted to use BOP for.