Reddit mentions: The best bsd operating system books

While being a self taught sys admin is great, learning the internals of how things work can really extend your knowledge beyond what you may have considered possible. This starts to get more into the CS portion of things, but who cares. It's still great stuff to know, and if you know this you will really be set apart. Im not sure if it will help you directly as a sys admin, but may quench your thirst. Im both a programmer and unix admin, so I tend to like both. I own or have owned most of these and enjoy them greatly. You may also consider renting them or just downloading them. I can say that knowing how thing operate internally is great, it fills in a lot of holes.

OS Internals

While you obviously are successful at the running and maintaining of unix like systems. How much do you know about their internal functions? While reading source code is the best method, some great books will save you many hours of time and will be a bit more enjoyable. These books are Amazing
The Design and Implementation of the FreeBSD Operating System

Linux Kernel Development
Advanced Programming in the UNIX Environment

Networking

Learning the actual function of networking at the code level is really interesting. Theres a whole other world below implementation. You likely know a lot of this.
Computer Networks

TCP/IP Illustrated, Vol. 1: The Protocols

Unix Network Programming, Volume 1: The Sockets Networking API

Compilers/Low Level computer Function

Knowing how a computer actually works, from electricity, to EE principles , through assembly to compilers may also interest you.
Code: The Hidden Language of Computer Hardware and Software

Computer Systems: A Programmer's Perspective

Compilers: Principles, Techniques, and Tools

> There has been pretty wide spread reporting on the kid hacking and getting 90 GB of private data

What I saw reported was:

• kid "hacked" Apple
  
• kid downloaded 90GB data
  
  Nothing said what he hacked or downloaded, just that he hacked something and downloaded "data". That could very well be a honeypot.
  
  > In China Apple has the China government keep the data instead of Google and not sure how good they are at security but I am sure a lot better then Apple at least.
  
  Again, source? With Apple being worth ~$1T, I'm sure they can hire a competent sysadmin.
  
  > Google has several of those people including Ken Thompson, Rob Pike and a bunch of other ones
  
  And they stopped working on Plan9 when they got hired, that was my point.
  
  > Here is why they get all the best engineers.
  >
  > https://www.cnbc.com/2018/09/12/23000-millennial-and-gen-z-workers-listed-their-dream-employers.html
  
  People want to work there because they pay really well. I wanted to work there when I was doing my undergrad, but that that faded and now I wouldn't take a job from them even if offered. I've read too many horror stories from people who worked there that it's just not worth my time.
  
  I do not trust Google, though I use their tech when it makes sense. I develop in Go, use Angular for some projects, and build stuff on Kubernetes. I also use competitor tech, like Rust and React.
  
  > We had AirPort extremes for example and replaced with Google WiFi.
  
  Why not something more mainstream like Linksys or Trendnet?
  
  > Google owns all the IP others use
  
  That's just not true.
  
  Oh, and they have retaliated with their own set of patents when challenged. They don't seem to want the publicity of being a patent troll. I think of this more as a business decision and less of a "we're the good guys" decision.
  
  > Waymo did with Uber.
  
  There are plenty of companies worse than Google, like Oracle (sued Google and a ton of others). I'm not saying that Google is "bad" (yet), just that they're not "good".
  
  > Only GOOGL gets voting and that means Brin and Page control, completely. They can NEVER be fired.
  
  What happens when they leave?
  
  > completely broken patent system in the US
  
  Agreed, we desperately need to fix (or completely eliminate) our patent system. Patents on software and designs are ridiculous.
  
  > Now what I find fascinating is that Google gave away majority of their IP. Poor business but good for everyone.
  
  No, it's a good business move. Their business is user data and mindshare, and that's how you get tech fanboys. It's a brilliant business move IMO.
  
  > BTW, my previous generation OS idle is David Cutler. But obviously before NT.
  
  I'm a fan of Kirk McKusick, if for nothing else than The Design and Implementation of the FreeBSD Operating System.
  
  I'm pretty hyped about Redox though.

Maybe a more concrete example will help. Here's a snapshot of the memory use of my main work machine:

Mem: 3269M Active, 2797M Inact, 1320M Wired, 362M Cache, 828M Buf, 169M Free

It's FreeBSD, but illustrative of how vaguely modern VM's work; as you suggest, it's not just "memory in use" and "memory that's free", there's a hierarchy through which pages are run through depending on use. In FreeBSD's case, Active is directly mapped into processes read-write, or cached stuff which has been recently used and likely to be wanted at a moment's notice.

Inact is inactive memory; the next level down. This mostly includes cached data which can either be pushed back into Active quickly if it's needed, or flushed out relatively quickly, or further migrated down the chain.

Cache is the next level down from Inactive; it's read-only, not directly mapped into anything, and almost as cheap to reuse as Free (but more expensive to reactivate than Inact if it is needed), which is where it's cycled next if there's sufficient memory pressure. Some Free is obviously good; a quick pool of pre-zeroed memory is pretty important.

Wired and Buf are mostly kernel; in my case most of Wired is ZFS's own kernel-malloc backed cache, but it also includes anything else that can't be swapped out, like vital kernel code and certain userspace things. e.g. gpg will try to lock memory which is sensitive and shouldn't hit unencrypted swap.

Point being; how much memory does this machine really have free? 169MB? What about the 362MB of Cache which is more or less ready for any new use? And I can probably dump most of that Inact without much trouble. And who's to say how much Active really needs to be there; without much memory pressure it's sure not going to work too hard working out what doesn't really need to be there.

It's been ages since I read the book, and I'm also tired and on prescription medication, so E&OE.

Cool! I'm not quite sure where you're at in your practice, so apologies if the following is old hat to you.

Books: Original Devil book, don't bother with the 4.4 one (http://www.amazon.com/Design-Implementation-Unix-Operating-System/dp/0201546299), Uresh Vahalia's UNIX Internals, the Lions book, Muchnick's Advanced compiler book, Patterson and Hennessy's CA:AQA, err. Probably some stuff I'm forgetting.

Projects: v8 (Google's JavaScript engine) is a beautiful program.

But mostly, practice. Practice can be more important than reading, especially if you get to practice around people who are better than you. If you have the chance to write your own operating system, you should do so. My experience with this, in Brown's CS 169, was literally life-changing.

It's a great book, many intro to Operating Systems classes use it. Although, a bit pricey (£112) they're plenty of copies that can be purchased used with a more manageable price tag.

There's also The Design and Implementation of the FreeBSD Operating System that is better served after reading Tanenbaum's primer.

Learning how to write device drivers for something like Linux is a good way to get started with the kind of low-level coding you're talking about without having to write a full blown OS from scratch.

This book about FreeBSD is pretty good too - http://amzn.com/0201702452 . It's pretty old, but apparently a new version is due out in September.

FreeBSD Unleashed is a fantastic book. Highly recommend for anyone new to Linux or Unix. I have the version 6 copy and I still reference it for current FreeBSD tasks.

Edit: FreeBSD 6 Unleashed

Excellent book!

You can't forget Tanenbaum: http://www.amazon.com/Modern-Operating-Systems-Andrew-Tanenbaum/dp/0136006639/ref=sr_1_1?s=books&ie=UTF8&qid=1302667905&sr=1-1

Or the design of the BSD operating system: http://www.amazon.com/Design-Implementation-FreeBSD-Operating-System/dp/0201702452/ref=sr_1_2?s=books&ie=UTF8&qid=1302667950&sr=1-2

Two Must-haves for any *nix // C guys out there!

This might be a good step by step way of doing it:

• Operating System Concepts
  
  
• Modern Operating Systems
  
• The Design and Implementation of the FreeBSD Operating System
  
• Developing Your Own 32-Bit Operating System
  
  Depending on skill and knowledge level you might want to skip the first two or one of them at least.

I dont now what you mean with original Unix, but 4.4BSD, released in 1977, already had more than 100 syscalls.

Last time I hacked a Kernel was for FreeBSD 6.0. I could literally use the book The Design and Implementation of the 4.4 BSD Operating System, released 1996, and the source code in the book are mostly identical to the FreeBSD kernel source code - except some fancy new technologies like SMP/locking support.

I have The Design and Implementation of the 4.4 BSD Operating System and, although I don't use BSD any more (except OS X on the desktop), I found it a very interesting read and I think it will be worth re-reading periodically.

I've heard good things about The Design and Implementation of the 4.4 BSD Operating System from the BSD folk. I imagine high-level concepts would carry over to the Linux kernel. Based on the reviews, it doesn't actually show any code, just pseudo-code and overview.

I have read [The Design and Implementation of the FreeBSD Operating System](http://www.amazon.com/Design-Implementation-FreeBSD-Operating-System/dp/0201702452/ref=sr_1_1?ie=UTF8&s=books&qid=1256868970&sr=8-1 "The BSD Book"). I agree that the operating system is much more elegantly designed than Linux. Well, it's just that this is a piss poor reason to actually use FreeBSD.

Of course, one has no trouble understanding why Apple chose to use BSD as the basis of Darwin.