You are aware that the code for full regression testing is bigger and requires more manpower than the code it tests? They've bought themselves into a testing nightmare. It's going to be regression after regression because there is no way they will have the time or the manpower or the inclination to do full regression testing before every release.
Maybe you have seen other instances where programming languages have been mashed up with big existing systems? Have you ever seen one of these that wasn't a nightmare? When I think of programming languages that offer extended capabilities, I think of Flash and Java and .Net, and all of these products are testing nightmares.
Last edited by frantaylor; 02-14-2013 at 04:55 PM.
The world of software development is littered with dead projects that died, not because of their technical inferiority, but simply because they could not be maintained. This is why microsoft and Oracle and RedHat deprecate old versions of their systems, it's because the maintenance headache exceeds the revenue. They don't want to fix your bugs because it's not worth it.
When you have no revenue and a massive maintenance headache, you end up putting the poor beast out of their misery because it's just too painful to go on, the pile of bugs gets too deep.
BSD relies on gifts and people feeling sorry for them, they have no actual revenue stream, no vendor commitment. They will get no vendor commitment, because the vendor doesn't need to commit, the vendor can just grab a snapshot and leave the project flapping.
I wonder how much of the internals get exposed vs sysfs on linux.
On one hand this sounds interesting, on the other I wonder about security...drivers in Lua sound interesting, especially from the standpoint of having one driver that works everywhere.
will tell you every parameter that every loaded module will accept input for, that you can then control via /etc/sysctl, /etc/modprobe.d/ or kernel parameter line. The nice thing about doing it over sysfs is that there's a certain level of sanity checking involved. You can still break stuff and in theory trash your hardware by pumping the wrong value into the module and it actually trying to do it (ex: telling your fans to run at max speed 24/7--youll kill your fans pretty quick, but you CAN do it via sysfs) but you probably wont crash the driver, unless you hit a bug, because it knows which parameters are ints, or arrays, or bool's and therefore you wouldnt get a driver crash because you pumped a "7" into a Bool, you'd either get an error or itd just ignore the invalid input and drop back to a sane default setting.Code:ls /sys/module/*/parameters/
You've heard of FUSE? The idea of FUSE came from Hurd.
The lesson here is that if you want to run interpreted drivers, then you need to lift the entire driver mechanism out of the kernel and put it into user space. This idea is kind of shocking at first. Yes all of the drivers. It's all or nothing, or else you end up with terrible performance problems, because passing data back and forth between kernel space and user space is ugly, and drivers need to talk to each other. Really you just map the piece of hardware into the driver's address space and you are all set. You dramatically reduce the "attack surface" of security vulnerabilities because the drivers are not in the kernel, they are running in user space as a very low privileged user. Successful attacks can result in denial-of-service but that's about it. You think about it some more and you realize that there's really no reason for a device driver to have access to everything in the whole computer, its scope is really quite limited, and that's what you get in user space. What you see happening here with BSD is that they see the beauty of the Hurd approach but they don't want to do the hard work of hoisting the device drivers out of the kernel. It's a very ugly hack.
The problem with the Hurd is that #1 they didn't think everything all the way through before they started coding, so there are some fundamental performance issues. Problem #2 is that it's a very very long way from "shippable product" quality and it's basically a "pet project" so it isn't getting serious developer manpower thrown at it. However you will learn a lot about computing if you read the design documents, and you can tell that if they ever get around to Hurd 2, it's going to be very very interesting.
The other thing to realize about the hurd is that it's one of the few operating system designs that's not based directly on the UNIX and VMS operating systems of the 1970s. If you think about it, the operating systems on all of our devices and computers today, nothing has changed much at all since the late 1970s. If you go back to that time you will find VAX and PDP-11 systems running Unix and VMS and they bear quite striking resemblance to our modern Linux and Windows systems. So Hurd (and maybe some other severely niche OSs) are really the only progress that's happened in operating systems in the last 50 years.
Last edited by frantaylor; 02-15-2013 at 12:49 AM.