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From Watanabe Maki <watanabe.m...@gmail.com>
Subject Re: minimum number of machines for RF=3
Date Thu, 07 Jul 2011 10:41:14 GMT
It is expected behaviour and not relate on number of node.
After the failed node bringing back, the ring will be busy by Hinted Handoff rewriting and
Read Repair. If you run repair, all your 3 nodes need to build Merkel Tree, compare the hash
values,  then transfer latest data to each other.

You can tune the HH, read repair to reduce performance impact on self healing activities.

maki

On 2011/07/07, at 18:10, david lee <iecanfly@gmail.com> wrote:

> hi guys,
> 
> is there a minimum(recommended) number of machines for RF=3?
> 
> i encountered a test result where 
> # of nodes = 3
> RF  =  3 
> CL.READ=QUORUM
> and when 1 node was taken out and back in after which node repair was run,
> the TPS dropped significantly.
> 
> is this behaviour expected since the RF (for the duration of when 1 node was taken out)
> is higher than the # of nodes?
> 
> cheers,
> david 


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