Alexey Zotov created CASSANDRA-5036:
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             Summary: Wrong description of 'setstreamthroughput' option
                 Key: CASSANDRA-5036
                 URL: https://issues.apache.org/jira/browse/CASSANDRA-5036
             Project: Cassandra
          Issue Type: Bug
          Components: Config, Documentation & website
    Affects Versions: 1.1.6
         Environment: Cassandra 1.1.6 (DataStax distribution)
            Reporter: Alexey Zotov
            Priority: Trivial


There is a typo in description of 'setstreamthroughput' option. It is measured 
in megabits per second. Page with wrong description:
http://www.datastax.com/docs/1.1/references/nodetool#nodetool-setstreamthroughput
Page with right description:
http://www.datastax.com/docs/1.1/configuration/node_configuration#stream-throughput-outbound-megabits-per-sec



Also I want to discuss possibility to reduce default value for this option. I 
think that 400 Mbs is too high for common cases. 

Preface:
This option is used only in case streams. There are two cases when streams are 
actual. They are rebuilding of a node and repair process. Let's skip first case 
and will talk only about the second. Let's imagine that we have replication 
factor 3.

Cross-datacenter connectivity case: 
When we start repair process it will borrow all network channel. Let's do some 
calculations. You start repair on an one node, e.g. 5 node (3 remote and 2 
local) should send us some data. Note that 3 of them are from remote 
datacenter. So 400 * 3 = 1,2 Gbs we should receive through WAN. I'm sure that 
it's too high.

I suggest to make it 2 times less.


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