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https://issues.apache.org/jira/browse/CASSANDRA-876?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13944446#comment-13944446
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Muhammad Adel commented on CASSANDRA-876:
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Is this issue still open for the latest version of Cassandra? As far as I
understand from reading different documentations and articles about MemTables
they are already searched for data before searching the SSTable when performing
a query.
> 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 CASSANDRA-569 has some (probably out of date now)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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