Plurrrr

Python is an object language. This is nice and cozy until you are out of memory holding 10 million objects at once. Let’s talk about how to reduce appetite.

FreeBSD Jails is a great piece of container technology pioneered several years before Solaris Zones. Not to mention 15 years before Docker was born. Today they still work great and offer some new features like entire network stack for each Jail called VNET. Unfortunately they also have downsides. For example anything related to NFS is broken inside FreeBSD Jails (especially when they are VNET based Jails) and the relevant 251347 Bug Report remains unsolved.

There is however a way to run NFS server inside VNET based FreeBSD Jail – we will use userspace NFS server implementation instead of using the FreeBSD base system kernel space NFS server. Its available as net/unfs3 package and this is exactly what we will gonna use for this guide.

Sometimes you just have a bunch of example data laying around and you want to make sure your code works with all of them. Some of them are probably short and sweet and could live happily as doctests, which are amazing btw. But some of them are more awkward to present in such form, because, for example, of their size or number. Typically when you have an example of how the program should behave you write an example-based unit test. Ideally, each of them would represent an isolated example and they should fail independently. But, converting your source data files into a unit test one by one, manually, can be a bit tedious.

Rust build scripts to the rescue !