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Date: Fri, 27 Aug 2010 15:23:33 +0200
From: Mikio Braun <mikio@cs.tu-berlin.de>
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To: user@cassandra.apache.org
Subject: Re: Follow-up post on cassandra configuration with some experiments
 on GC tuning
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Dear all,

thanks for your comments, and I'm glad that you found my post helpful.

Concerning the incremental CMS, I've recently updated my post and added
the experiments repeated on one of our cluster nodes, and for some
reason incremental CMS doesn't look that different anymore. So I guess
it's ok to stick with the non-incremental CMS for now.

- -M

On 08/27/2010 09:12 AM, Peter Schuller wrote:
>> Whether or not this is likely to happen with Cassandra I don't know. I
>> don't know much about the incremental duty cycles are scheduled and it
>> may be the case that Cassandra is not even remotely close to having a
>> problem with incremental mode.
> 
> I should further weaken my statement by pointing out that I never did
> any exhaustive tweaking to get around the problem (other than
> disabling incremental mode, since my primary goal has tended to be
> ensure low pause times and not so much even GC activity). It may be
> the case that even in stressful cases where it fails by default it is
> simply a matter of tweaking.
> 
> So, I guess I should re-phrase: In terms of just turning on
> incremental mode without at least application specific tweaking (if
> not deployment specific testing), I would suggest caution.
> 
> 


- -- 
Dr. Mikio Braun                        email: mikio@cs.tu-berlin.de
TU Berlin                              web: ml.cs.tu-berlin.de/~mikio
Franklinstr. 28/29                     tel: +49 30 314 78627
10587 Berlin, Germany


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