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From Robert Coli <>
Subject Re: horizontal query scaling issues follow on
Date Thu, 17 Jul 2014 22:58:17 GMT
On Thu, Jul 17, 2014 at 3:21 PM, Diane Griffith <>

> So do partitions equate to tokens/vnodes?

A partition is what used to be called a "row".

Each individual token in the token ring can contain a partition, which you
request using the token as the key.

A "token range" is the space between two tokens.

> If so we had configured all cluster nodes/vms with num_tokens: 256 instead
> of setting init_token and assigning ranges.  I am still not getting why in
> Cassandra 2.0, I would assign my own ranges via init_token and this was
> based on the documentation and even this blog item
> <> that
> made it seem right for us to always configure our cluster vms with
> num_tokens: 256 in the cassandra.yaml file.

If you are using vnodes and don't want to try to figure out what ideally
random token ranges for them are, you should, generally :

1) start the node with num_tokens set to a value greater than 1
2) once succesffully bootstrapped, dump all node tokens with :

nodetool info -T | grep Token | awk '{print $3}' | paste -s -d,

3) put list from 2) in initial_token list in cassandra.yaml
4) (optional) restart and verify that your node has the tokens you expect

So given that I was assuming the partitions were such that it wasn't a
> problem.  Is that an incorrect assumption and something to dig into more?

How many client threads do you have? Your OP suggested a low number, which
will not have good results in terms of throughput?


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