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From Darren Smythe <darren1...@gmail.com>
Subject Re: 1.2 tuning
Date Wed, 05 Jun 2013 21:54:55 GMT
Hi-

On Mon, Jun 3, 2013 at 10:36 AM, Robert Coli <rcoli@eventbrite.com> wrote:

> On Mon, Jun 3, 2013 at 8:54 AM, Darren Smythe <darren1482@gmail.com>
> wrote:
> > Is "setting live ratio to minimum of 1.0 instead of X" supposed to be
> rare?
> > Because were getting it fairly consistently.
>
> Do you have working JNA? If so, my understanding is that message
> should be relatively rare..
>


We recently tried a 8 xlarge node cluster instead of just 4 xlarge
instances, keeping the number of clients the same as before. But were still
seeing a lot of "setting live ratio" and "flush up to the two largest
memtables" messages alot. The compaction queues still seem congested also.

Theere's also alot of dropped MUTATION messages --- 13,000,000 Completed in
Mutation Stage, 100,000 Dropped

THe inserts are now about 11k/second, up slightly from 10k/second with 4
nodes.

Another missing piece may be that each column has a 1-2k blob as a value.
The value is binary now, but were moving to json later.

TIA
--Darren


>
> ./src/java/org/apache/cassandra/db/Memtable.java
> "
>               double newRatio = (double) deepSize / currentSize.get();
>
>                     if (newRatio < MIN_SANE_LIVE_RATIO)
>                     {
>                         logger.warn("setting live ratio to minimum of
> {} instead of {}", MIN_SANE_LIVE_RATIO, newRatio);
>                         newRatio = MIN_SANE_LIVE_RATIO;
>                     }
> "
>
> =Rob
>

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