We use CQL with 1 session per client and default connection settings. I do not think that we are using too many client threads. Number of native transport threads is set to default (max 128).
From: Robert Coli [mailto:rc...@eventbrite.com] Sent: den 21 november 2014 19:30 To: user@cassandra.apache.org Subject: Re: high context switches On Fri, Nov 21, 2014 at 1:21 AM, Jan Karlsson <jan.karls...@ericsson.com<mailto:jan.karls...@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
