number of thread pools

[Ross Brown]

> Why is it advised for Varnish 3 to only run with 2 thread pools rather than a thread pool per cpu core?

The thread model allows you to use multiple thread pools, but time and experience has shown that as long as you have 2 thread pools, adding more will not increase performance.

The most important thread setting is the number of worker threads.

Note If you run across tuning advice that suggests running one thread pool for each CPU core, res assured that this is old advice. Experiments and data from production environments have revealed that as long as you have two thread pools (which is the default), there is nothing to gain by increasing the number of thread pools.

From https://www.varnish-software.com/static/book/Tuning.html#threading-model