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From aaron morton <aa...@thelastpickle.com>
Subject Re: active/pending queue lengths
Date Mon, 13 Feb 2012 19:06:43 GMT
What CL are you reading at ? 

Write ops go to RF number of nodes, read ops go to RF number of nodes 10% (the default probability
that Read Repair will be running) of the time and CL number of nodes 90% of the time. With
2 nodes and RF 2 the QUOURM is 2, every request will involve all nodes. 

As to why the pending list gets longer, do you have some more info ? What process are you
using to measure ? It's hard to guess why. In this setup every node will have the data and
should be able to do a local read and then on the other node. 

Cheers 

 
-----------------
Aaron Morton
Freelance Developer
@aaronmorton
http://www.thelastpickle.com

On 14/02/2012, at 12:47 AM, Franc Carter wrote:

> 
> Hi,
> 
> I've been looking at tpstats as various test queries run and I noticed something I don't
understand.
> 
> I have a two node cluster with RF=2 on which I run 4 parallel queries, each job goes
through a list of keys doing a multiget for 2 keys at a time. If two of the queries go to
one node and the other two go to a different node then the pending queue on the node gets
much longer than if they all go to the one node.
> 
> I'm clearly missing something here as I would have expected the opposite
> 
> cheers
> 
> -- 
> Franc Carter | Systems architect | Sirca Ltd
> franc.carter@sirca.org.au | www.sirca.org.au
> Tel: +61 2 9236 9118 
> Level 9, 80 Clarence St, Sydney NSW 2000
> PO Box H58, Australia Square, Sydney NSW 1215
> 


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