I like learn, explain and, when time gives me a chance, write. Write and transmit knowledge is complicated and requires time, at least for me, to structure what to say and how to say it.
As Albert Einstein said: If you can't explain it simply, you don't understand it well enough.
The NodeJS cluster module is a short book, extracted from this post articles, introducing the NodeJS cluster module. NodeJS processes runs on a single process, which means it does not take advantage from multi-core systems by default. If you have an 8 core CPU and run a NodeJS program via $ node app.js it will run in a single process, wasting the rest of CPUs.
Hopefully for us NodeJS offers the cluster module that contains a set of functions and properties that help us to create programs that uses all the CPUs.
LeanPub link: https://leanpub.com/thenodejsclustermodule
The Book of OpenLayers3: Published on 2014, just before the first release of OpenLayers3 was release, the book covers the most important topics of this awesome web mapping library.
LeanPub link: https://leanpub.com/thebookofopenlayers3