PDF is a family of standards. There's a core specification and a set of extensions (including, somewhat confusingly, some that remove functionality). In particular, PDF/A removes some of the crazy things (embedded video, audio and JavaScript) and is intended for archiving. Adobe is the driving force behind the standard, and do add non-standard things to their tools (although via a well-defined extension interface), but they're very careful to differentiate PDF/A because a lot of their deep-pocketed customers care a lot about PDF/A as a long-term archive medium. The vested interests of various governments in PDF/A mean that Adobe will have a hard time pushing things through ISO that would be bad for the standard.

It differs a bit depending on what the graduate course is. I'm not entirely sure how this translates to the US system, but in the UK you basically have three or four categories (depending on how you count). Taught masters, which are basically an extra year of an undergraduate degree. These come in two flavours, the conventional and the 'conversion' variant, the latter being aimed at people who didn't do an undergraduate course in the same subject (e.g. people who did a degree in maths wanting to study physics). The former is generally a chance to specialise and so should involve a lot of choice. By the time the student arrives, they're expected to know what the field contains and have decided that a particular subfield is really interesting. The latter has largely the same goals as the undergraduate degree: to give a whirlwind tour of the subject to someone who is expected to have already learned how to teach themselves and allow them to pick up the bits that they might want to know later.

The other two categories are the doctorates and untaught masters. These have basically the same structure: you'll work on something original (and typically very specialised). The amount of originality and the scope of the project differs between the doctorate and the masters (often the masters is awarded to people who fail the PhD - if you get a few years in to a PhD you can apply to be assessed as an MPhil instead, so it's not completely wasted time). Here the supervisor is responsible for providing a bit of direction, but the project is largely driven by the student because, again, they're expected to already have a broad knowledge of the subject (but not necessarily of the specialised field).

NIC drivers interact directly with the network stack only via a set of well-defined interfaces (in FreeBSD at least), and writing the drivers is a one-shot operation because for new purchases they can demand FreeBSD drivers and support from their vendors (as Netflix, Verisign, and others do already). In the networking space, enough big companies are already demanding FreeBSD support for the high-end cards that the drivers are already likely to exist, so the missing ones are likely to be other things.

Your comparison doesn't make sense. Sure, a tank of petrol is denser than a battery, but a machine to turn the output of a solar cell into petrol isn't, and the machine to take that power and turn it back into something your house's electrical system can use (with little loss) is also big. Connecting your car's fuel tank up to both machines every time you park is not feasible. In contrast, connecting a power cable to your battery is pretty easy.

That's why they think Tesla is likely to be disruptive. Every electric car has a big electrical storage device attached. When your car is parked, you can use it to store excess electricity. If you're not going on a long trip the next day, you can use it to power your house overnight. If you are, then your neighbours probably aren't, so there's still spare storage capacity near you.

Snow is a very good insulator. You don't need to be leaking much heat to eventually heat up the thing underneath it to above freezing and then eventually melt the snow. Even a complete vacuum won't do it.

You say $10bn, the grandparent says $107.3bn. Either your talking about different things, or one of you has their numbers very wrong.

Out of interest, how many cores are you using? I've not used Solaris for... a long time, but their network stack was redesigned a little while ago to do each layer in a different thread with lockless ring buffers between them all. I'd imagine latency might suffer a bit, but throughput should be insane with enough hardware contexts. On something like the UltraSPARC Tx series, I'd expect it to outperform FreeBSD, but I've never seen numbers.

How much of Facebook's code is not platform-independent already? Most of their web infrastructure is PHP with a custom compiler. The compiler may need some tweaks, but the PHP code that it compiles should be completely independent. Drivers are a different issue, but if they're employing a load of kernel devs it's a lot easier to write a few missing drivers than make large and invasive changes to the network stack.

While this is technically true, we recently had a PhD student try this. First, the Linux version is only available as patches so it took him a while to find a version of Linux that they'd apply against. Once he'd done this, it turns out that the driver support is basically only there in Linux for Intel NICs, which are modified as part of the patch. In FreeBSD, because it's merged into trunk, most NIC drivers support it.

Oh, and Adrian isn't at Netflix anymore, but he's still working on networking stuff (now at one of the CDN companies, but I forget which one).

It's a common misconception that any code that you link with Linux has to be GPL'd. The GPL only requires that linked code has no restrictions not present in the GPL and that the combined work is covered by the GPL. Individual components can be in one of several more permissive licenses. The Linux kernel already contains fairly large amounts of BSDL and similar code.

It's not so much about learning things they don't want to learn as about learning things that they don't even know exists. When I arrived at university, I'd been programming for over 10 years and thought I knew most of the stuff I'd be expected to learn. I didn't even know graph theory or complexity theory existed and they've both been phenomenally useful since I graduated. There was a load of other stuff (logic programming and functional programming, for example) that I've used but didn't really know were subjects that I might want to study when I arrived.

A small proportion of stuff in my degree (mostly stuff in the first six months) was stuff I already knew when I arrived. Maybe 30-40% was stuff I knew I didn't know much about and wanted to learn. The rest was all stuff that I didn't even know that I didn't know. I probably could have taught myself most of it if I'd known that the subjects existed (I now do research involving compilers and computer architecture and had a single [very badly taught] compilers module as a student and a single architecture course that gave a very brief overview of the subject) but the value in the degree was showing me the things that I might want to teach myself.

The network stack is a complex bit of code that interacts in complex ways with the scheduler, the generic locking frameworks, the driver infrastructure, the bus and DMA, infrastructure and everything up to the system call layer. The device drivers are self-contained and (individually) small pieces of code. Which do you think is cheaper and easier to modify?

Quite a few consumer router manufacturers actually ship Linux with the FreeBSD network stack grafted onto it. I don't know why.