Thank you for this. I know what I'm reading for the next two months!
In your original post, you mention one of the goals being able to contribute a patch to a modern OS such as BSD or Linux. After your experiment, do you feel like this is the case?
In your original post, you mention one of the goals being able to contribute a patch to a modern OS such as BSD or Linux. After your experiment, do you feel like this is the case?
I feel like I could after maybe ~30h (really I don't have enough information to determine beyond it probably being between 10 and 100 hours) of focused effort. I did read a bunch of The Design and Implementation of FreeBSD and I felt like I could understand it reasonably well, using the mental models I picked up studying xv6.
The reasons why I didn't do it (yet) are interesting in themselves. There was nothing in particular that I felt was missing from FreeBSD, and I hadn't used the "advanced" parts of the OS enough to run into any bugs. Because of this I think I lacked a sense of ownership, and the artificiality of a bug hunting activity caught up to me, motivation-wise. To do this I think you need to be motivated to dive into the nitty-gritty of a particular part of the OS, in addition to having a good understanding of the OS as a whole. Instead I ended up exploring some of the more advanced parts of FreeBSD (Jails and ZFS) with http://experiments.oskarth.com/netpowder/ - hopefully I will find something useful that I want to either extend or a bug I want to fix, or perhaps I get to test the hypothesis with something completely different (such as Mirage OS).