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From Robert Coli <rc...@eventbrite.com>
Subject Re: high context switches
Date Fri, 21 Nov 2014 18:29:42 GMT
On Fri, Nov 21, 2014 at 1:21 AM, Jan Karlsson <jan.karlsson@ericsson.com>
wrote:

>  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?
>

I +1 Nikolai's conjecture that you are probably using a very high number of
client threads.

However as a general statement Cassandra is highly multi-threaded. Threads
are assigned within thread pools and these thread pools can be thought of
as a type of processing pipeline, such that one is often the input to
another. When pushing Cassandra near its maximum capacity, you will
therefore spend a lot of time switching between threads.

=Rob
http://twitter.com/rcolidba

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