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https://issues.apache.org/jira/browse/CASSANDRA-2677?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Jonathan Ellis reassigned CASSANDRA-2677:
-----------------------------------------

    Assignee:     (was: Sylvain Lebresne)

> Optimize streaming to be single-pass
> ------------------------------------
>
>                 Key: CASSANDRA-2677
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-2677
>             Project: Cassandra
>          Issue Type: Improvement
>          Components: Core
>            Reporter: Jonathan Ellis
>            Priority: Minor
>             Fix For: 0.8.2
>
>
> Streaming currently is a two-pass operation: one to write the Data component 
> do disk from the socket, then another to build the index and bloom filter 
> from it.  This means we do about 2x the i/o we would if we created the index 
> and BF during the original write.
> For node movement this was not considered to be a Big Deal because the stream 
> target is not a member of the ring, so we can be inefficient without hurting 
> live queries.  But optimizing node movement to not require un/rebootstrap 
> (CASSANDRA-1427) and bulk load (CASSANDRA-1278) mean we can stream to live 
> nodes too.
> The main obstacle here is we don't know how many keys will be in the new 
> sstable ahead of time, which we need to size the bloom filter correctly. We 
> can solve this by including that information (or a close approximation) in 
> the stream setup -- the source node can calculate that without hitting disk 
> from the in-memory index summary.

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