From a public cloud big enough to make Jeff Bezos crap his pants, down to a single-node DevStack environment under VirtualBox, this talk will cover why scale matters and what you must take into account when planning an OpenStack deployment. Scalability details of specific OpenStack components (compute, block and object storage, and networking), their inherent limits, and effective workarounds will be discussed along with a review of a few deployments that worked and others that didn’t.