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https://issues.apache.org/jira/browse/CASSANDRA-876?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Jonathan Ellis resolved CASSANDRA-876.
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    Resolution: Won't Fix

Going to close as wontfix; I don't see "be careful not to do too many writes in 
your session or you'll OOM because we're saving them for CL.RYW" as a fun 
explanation to give people.

> Support session (read-after-write) consistency
> ----------------------------------------------
>
>                 Key: CASSANDRA-876
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-876
>             Project: Cassandra
>          Issue Type: New Feature
>          Components: Core
>            Reporter: Jonathan Ellis
>            Priority: Minor
>              Labels: gsoc, gsoc2010
>         Attachments: 876-v2.txt, CASSANDRA-876.patch
>
>
> In http://www.allthingsdistributed.com/2007/10/amazons_dynamo.html and 
> http://www.allthingsdistributed.com/2008/12/eventually_consistent.html Amazon 
> discusses the concept of "eventual consistency."  Cassandra uses eventual 
> consistency in a design similar to Dynamo.
> Supporting session consistency would be useful and relatively easy to add: we 
> already have the concept of a Memtable (see 
> http://wiki.apache.org/cassandra/MemtableSSTable ) to "stage" updates in 
> before flushing to disk; if we applied mutations to a session-level memtable 
> on the coordinator machine (that is, the machine the client is connected to), 
> and then did a final merge from that table against query results before 
> handing them to the client, we'd get it almost for free.
> Of course, the devil is in the details; thrift doesn't provide any hooks for 
> session-level data out of the box, but we could do this with a threadlocal 
> approach fairly easily.  CASSANDRA-569 has some (probably out of date now) 
> code that might be useful here.



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