This blog is mostly about Linux-related topics but from time to time covers interesting other OS-related technology. One such interesting new technology is OSv, which was designed from the ground up to execute a single application on top of a hypervisor, resulting in superior performance and effortless management.
Developed by a number of the initial developers of KVM, including Avi Kivity, OSv was designed to give near-hardware level access efficiency for Java VMs. OSv also reduces the memory and CPU overhead imposed by traditional OSes. Evidently ZFS is the default filesystem.
Interestingly, OSv is implemented in C++, using templates, which is probably the last language and paradigm I would consider if I had to design an OS from scratch. According to their FAQ,
Aren’t there enough operating systems written in C? Let’s give another language a chance.
While C++ has a deserved reputation for being incredibly complicated, it is also incredibly rich and flexible, and in particular has very a flexible standard library as well as add-on libraries such as boost. This allows OSv code to be much more concise than it would be if it were written in C, while retaining the close-to-the-metal efficiency of C.
Hmm, I do not think that is sufficient rational for choosing C++.
Feeling adventurous? OSv is licensed under a 3-clause BSD-style license and can be downloaded from their website.