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From Robert Coli <rc...@eventbrite.com>
Subject Re: Tune MemTable per column Family
Date Mon, 16 Sep 2013 19:34:26 GMT
On Mon, Sep 16, 2013 at 12:01 PM, Philippe <watcherfr@gmail.com> wrote:

> Is there a way to limit the Memtable sizes on a columnFamily basis on
> cassandra 1.1.x ? I have some CF that have very very low throughput and I'd
> like to lower the amount of data in memory to keep the Heap size down.
>

No.

If you wanted to, you could simply trigger a flush of these CFs via JMX
periodically.

In 1.0, there is a mechanism by which these CFs are motivated to flush,
when they fragment the commit log too much.

https://issues.apache.org/jira/browse/CASSANDRA-2427

In 2.0, there is a re-introduction of the time based bound for memtables
which allows you to automatically flush after a fixed time... but it is
still a global setting.

https://issues.apache.org/jira/browse/CASSANDRA-4237

memtable_flush_period_in_ms

=Rob

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