“At its core, Heroku is just a simple unix platform; specifically, Ubuntu 10.04 LTS…”
“The entire Heroku platform is really nothing more than small Ubuntu virtual server instances that can be spun up and down on demand. Each instance (Heroku calls them dynos), has:
– 512MB of RAM, 1GB of swap. Total = 1.5GB RAM.
– 4 CPU cores (Intel Xeon X5550 @ 2.67GHz).
– Isolated execution. Anything you store on your dyno will be isolated from all other dynos. A chroot jail environment. This means that you are completely locked down to one directory tree, with no write access to system files…”