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From Nikolai Grigoriev <ngrigor...@gmail.com>
Subject Re: high context switches
Date Fri, 21 Nov 2014 14:13:37 GMT
How do the clients connect, which protocol is used and do they use
keep-alive connections? Is it possible that the clients use Thrift and the
server type is "sync"? It is just my guess, but in this scenario with high
number of clients connecting-disconnecting often there may be high number
of context switching.

On Fri, Nov 21, 2014 at 4:21 AM, Jan Karlsson <jan.karlsson@ericsson.com>
wrote:

>  Hello,
>
>
>
> We are running a 3 node cluster with RF=3 and 5 clients in a test
> environment. The C* settings are mostly default. We noticed quite high
> context switching during our tests. On 100 000 000 keys/partitions we
> averaged around 260 000 cs (with a max of 530 000).
>
>
>
> We were running 12 000~ transactions per second. 10 000 reads and 2000
> updates.
>
>
>
> Nothing really wrong with that however I would like to understand why
> these numbers are so high. Have others noticed this behavior? How much
> context switching is expected and why? What are the variables that affect
> this?
>
>
>
> /J
>



-- 
Nikolai Grigoriev
(514) 772-5178

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