Dan Callaghan

Linux.conf.au 2020: day two

Following on from the previous post, these are the talks I attended on day two of Linux.conf.au 2020, which was the second day of miniconfs.

Drop your tools: does expertise have a dark side? – Sean Brady

A captivating and well-rehearsed speaker. He recounted the history of the Mann Gulch fire and tied it back to the psychological phenomenon of “negative priming”: when you’re an expert in something it biases your brain away from finding novel solutions that fall outside your expertise. In the case of the fire, it was the trained firefighters who could not give up the idea that they must always carry their tools, even though they were weighing them down. Bringing it closer to home, he also mentioned the Hartford Civic Centre roof collapse which was caused by engineers placing too much trust in their (computerised) calculations. His thesis was that we need to beware of when our expertise is blinding us to better solutions.

FreeBSD: the other UNIX-like operating system and why you should work together – Deb Goodkin

This talk kicked off the FreeBSD mini-conf. She presented some history of the provenance of the BSDs. FreeBSD uses a normal contribution process and “modern tools” (this seems like a stretch, given they are still on Subversion). She emphasised that FreeBSD has no BDFL, which seemed to be a thinly veiled reference to Linus and his reputation as a grumpy asshole.

Netflix’s CDN is on FreeBSD, they implemented some special “async sendfile” support in nginx for it.

She then invited a FreeBSD committer, Philip Paeps, onto stage and his tone was quite different. He used the phrase “our kernel” and “our code” a lot and he seemed to suffer the typical underdog defensive attitude towards Linux. He made many derogatory (and ultimately baseless and unhelpful) comparisons to Linux, like: FreeBSD is a “complete integrated system” that is “maintained together” (unlike the mess that is Linux). It follows “our principle of least astonishment” (unlike the continual surprises you get in Linux). And so forth. A very tone-deaf attitude to take when you are literally presenting at a Linux conference.

Back to Deb for the summary: the Linux community should be interested in FreeBSD because it brings diversity of ideas and approaches.

Introduction to FreeBSD ports: 25 years on – Ben Woodward

About half history of the ports tree, half practical examples of how add a package to the tree. He approached this as if it were totally unfamiliar to the audience but since I have done so much distro packaging in the past there was not much of interest here.

Ports maintainers use Bugzilla 4 and they post patches to it. Linux distro maintainers from the 2000s would feel right at home.

Poudriere got a brief mention at the very end – apparently a new(ish?) online service to handle isolated, reproducible builds of binary packages from the ports tree. Presumably similar to what all the Linux distros have used to build their packages for a very long time (Koji, OBS, etc).

The ZFS filesystem – Philip Paeps

This is what the talk about ZFS on day 1 should have been. A technical walk-through of ZFS’s feature set with a dip into how it stores data. One thing which stood out is that the filesystem somehow maintains a Merkle tree of all file data, not just individual block checksums, which gives much stronger integrity guarantees than something like LUKS integrity in Linux.

How an Australian IaaS uses FreeBSD - Ruben Schade

I attended this one mostly because I didn’t know we had any IaaS providers in Australia. It is called OrionVM and I had never heard of it. It turns out that’s because it’s a “wholesaler” which third parties can re-brand and on-sell as their own cloud offering (he mentioned some telcos).

This was light on technical details and more just spruiking the fact that their cloud offering can do FreeBSD and he likes recommending it for clients. ZFS is the big selling point. He mentioned some FreeBSD features that make good use of ZFS: Poudriere, iocage, ez-jail, and atomic upgrades. He didn’t explain any of them, it is left as further research for the reader.

He made a condescending comment about disliking Linux because the man pages refer you to GNU info. Another example of unhelpful attitudes in the FreeBSD community. Obviously GNU info is impossible to use and nobody on Linux uses it which is why all the distros have sunk effort into fleshing out the man pages to be complete and usable on their own (I would say, now rivalling the BSD ones in most cases).

LPI, BSD, WTF? – G Matthew Rice

Not a talk, should never have appeared on the schedule. I only sat in the room because I didn’t know what LPI was. It turns out it is the Linux Professional Institute which is a courseware and accreditation provider for entry-level sysadmin qualifications. They are doing BSD now.

At this point I went to the beach and skipped out on the rest of the FreeBSD miniconf. I think it was the right choice.