A flock of birds. Literally.
Michael Hausenblas
Oct 11, 2015 · 2 min read

Unless you’ve been living under a rock, I’m certain you’ve come across the pets vs cattle meme. Essentially it’s about treating machines in a cluster anonymously rather than as individuals.


I think there’s a new, emerging category: the flock of birds. Two prominent examples of this category are:

Sometimes these offerings are called (confusingly?) ‘server-less’ and the main selling point seems to be that you don’t think in terms of entire machines anymore — no matter if a physical machine, a virtual machine or a containerized environment — but really the unit of compute is a single function that you can execute, either per name or anonymously.


This new paradigm seems extremely powerful and for certain use cases very well suited. As a reminder and summary, here are the different schools of thinking concerning ‘compute’ (from most old-school to most modern):

  1. The unit of compute is a statically provisioned physical machine in a static partition setup. [[PETS]]
  2. The unit of compute is a statically provisioned virtual machine in a static partition setup. [[PETS]]
  3. The unit of compute is a statically provisioned container on a physical or virtual machine, in a static partition setup. [[CATTLE|PETS]]
  4. The unit of compute is a dynamically provisioned container on a physical or virtual machine, in a dynamic partition setup. [[CATTLE]]
  5. The unit of compute is a (potentially anonymous) function with dynamically allocated resources. [[FLOCK OF BIRDS]]

What do you think? Are there others? Where will this lead us and what are the consequences of this development?

Michael Hausenblas

Written by

Developer Advocate at AWS | Gopher | Cloud Native Ambassador | Kubernetes | containers

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