Unikernels are application sized virtualization like a container but use a unique kernel and OS like with a virtual machine. They are an image that contains a library operating system that can be directly be run on a hypervisor.
Unikernels are single-purpose virtual machines (VM). They only run one application—which is interesting when you think about it, because that’s precisely how a lot of DevOps practitioners provision their applications today. There is way too much software to provision nowadays—pools of app servers, clusters of databases, etc. Unikernels are fast to boot, fast to run, small in size, way more secure than Linux or containers and, if you have access to your own bare metal—either in your data center or through a provider—you can run thousands of them per box.
Some stats? Some can boot in less than five milliseconds—that’s slightly slower than calling fork (three milliseconds) but orders of magnitude faster than Linux. Some can run databases including Cassandra and MySQL, 20 percent faster. Some people (yours truly included) have provisioned thousands of them on a single box with no performance degradation. Some are reporting them running as a VM faster than a comparable bare-metal Linux installation of that application. Clearly, this is worth investigating.
There is a nice article:
