Dockers beats VMware when you have similar workloads - 20 to 80% lighter -> 25% to 500% more performance?

Gigaom’s Jonathan Vanian interviews Docker’s CEO Ben Golub and posts on June 27, 2014.  I had a chance to talk to Jonathan before he interviewed Ben and I had a simple question.  If you have a 100 servers running workloads that would fit in a Dockers environment how much better is Dockers vs. a typical virtualized environment?    Here is what Jonathan wrote up.

If an organization has 100 applications that are only slightly different from each other, it doesn’t have to spin up 100 virtual machines to house each application, thus saving a ton of overhead that comes with spinning up so many operating systems.

Depending on the situation, using containers can result in workloads that are 20 to 80 percent lighter than an equivalent workload using only virtual machines, according to Golub.

How can Docker be smaller than a VM?  Microsoft in its support for Docker writes an explanation.

Docker containeraization

By making Docker containers significantly smaller than traditional VMs, they can be booted/restarted more quickly, more of them can run on a single host and they are considerably more portable. Furthermore, when capturing a new Docker container, the tooling only needs to capture the differences between the original and the new container. This makes it possible to rationalize Docker as a kind of version control system for disk images.

One simple assumption you can make is if something is lighter with its size there is a 1-1 relationship between being lighter means you should be able to be more efficient.  If you are 20% lighter, than you can do 25% more work with the same capacity.  If you are at the extreme of 80% lighter, then you can do 500% more work with the same capacity of server hardware.  

As time goes on we’ll hopefully see real world results of how much more efficient Docker is than a hypervisor virtualization strategy.

Disclosure: I work for Gigaom Research as a part-time freelance analyst.