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https://issues.apache.org/jira/browse/CASSANDRA-9194?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14505760#comment-14505760
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Jonathan Ellis commented on CASSANDRA-9194:
-------------------------------------------

I figured that in 2.0 it will self-correct via liveRatio, so it doesn't really 
matter what constant we use.

> Delete-only workloads crash Cassandra
> -------------------------------------
>
>                 Key: CASSANDRA-9194
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-9194
>             Project: Cassandra
>          Issue Type: Bug
>         Environment: 2.0.14
>            Reporter: Robert Wille
>            Assignee: Benedict
>             Fix For: 2.0.15
>
>         Attachments: 9194.txt
>
>
> The size of a tombstone is not properly accounted for in the memtable. A 
> memtable which has only tombstones will never get flushed. It will grow until 
> the JVM runs out of memory. The following program easily demonstrates the 
> problem.
> {code}
>               Cluster.Builder builder = Cluster.builder();
>               
>               Cluster c = 
> builder.addContactPoints("cas121.devf3.com").build();
>               
>               Session s = c.connect();
>                       
>               s.execute("CREATE KEYSPACE IF NOT EXISTS test WITH replication 
> = { 'class' : 'SimpleStrategy', 'replication_factor' : 1 }");
>               s.execute("CREATE TABLE IF NOT EXISTS test.test(id INT PRIMARY 
> KEY)");
>               PreparedStatement stmt = s.prepare("DELETE FROM test.test WHERE 
> id = :id");
>               int id = 0;
>               
>               while (true)
>               {
>                       s.execute(stmt.bind(id));
>                       
>                       id++;
>               }{code}
> This program should run forever, but eventually Cassandra runs out of heap 
> and craps out. You needn't wait for Cassandra to crash. If you run "nodetool 
> cfstats test.test" while it is running, you'll see Memtable cell count grow, 
> but Memtable data size will remain 0.
> This issue was fixed once before. I received a patch for version 2.0.5 (I 
> believe), which contained the fix, but the fix has apparently been lost, 
> because it is clearly broken, and I don't see the fix in the change logs.



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