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https://issues.apache.org/jira/browse/CASSANDRA-4175?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13678132#comment-13678132
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Edward Capriolo commented on CASSANDRA-4175:
--------------------------------------------

Trying to generate atomic cross node auto_ids or using zookeeper for 
coordination of this seems to go against the entire eventual consistency model 
of cassandra. 

Why not have a node-local map and use murmur hash.

Also silly question. But if your columns are named 'pw' instead of 'password' 
aren't you more optimized then a 32bit or 64 bit integer anyway?


                
> Reduce memory (and disk) space requirements with a column name/id map
> ---------------------------------------------------------------------
>
>                 Key: CASSANDRA-4175
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-4175
>             Project: Cassandra
>          Issue Type: Improvement
>            Reporter: Jonathan Ellis
>             Fix For: 2.1
>
>
> We spend a lot of memory on column names, both transiently (during reads) and 
> more permanently (in the row cache).  Compression mitigates this on disk but 
> not on the heap.
> The overhead is significant for typical small column values, e.g., ints.
> Even though we intern once we get to the memtable, this affects writes too 
> via very high allocation rates in the young generation, hence more GC 
> activity.
> Now that CQL3 provides us some guarantees that column names must be defined 
> before they are inserted, we could create a map of (say) 32-bit int column 
> id, to names, and use that internally right up until we return a resultset to 
> the client.

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