Samuel J. Greear <s...@evilcode.net> wrote: > What has drawn you to use the DragonFly BSD operating system and/or > participate in its development by following this list? Technical > features, methodologies, something about the community?
First of all, I'm a FreeBSD user (since 2.0.5), and I'm not using DragonFly BSD for production. However, I installed it in a qemu instance for "playing" because I'm interested in it from a technical point of view. When DragonFly BSD forked from FreeBSD in the 4.x days, I was fascinated by Matt's announcement and the declaration of goals, in particular his SSI "vision". At that time, I thought that a working SSI cluster based on BSD technologies would be the coolest thing on earth. So I subscribed to the DF mailing lists (or rather, to the NNTP groups) and started to "watch the game". Another incentive was Matt's plan to implement a message- passing system inside the kernel, similar to what is used in AmigaOS. Having an Amiga background myself -- just like Matt -- I found this very interesting. I was curious how it would work out. Over the years, DragonFly BSD grew several features that were not present in FreeBSD, and which I found useful or interesting, such as variant symlinks (I still miss them very much in FreeBSD), process checkpointing (extremely cool, but needs some improvement to make it work better in practice), UFS journal streams, swapcache, and of course vkernel and HAMMER. Today I think that the SSI goal has become less important. The "cluster hype" has diminished and been partially replaced by the "cloud hype". Today, it is extremely important to have excellent SMP scalability. Multi-core systems are common, my desktop at home is a 6-core AMD Phenom II X6 which costs less than 200 Euros. You can buy x86 machines with 4 CPU sockets, 8 cores each, plus hyperthreading, so you get a 64-way SMP system. I think DragonFly BSD doesn't support these (yet), but don't worry, FreeBSD doesn't either. ;-) (They just upped the limit to 32-way in 9-current.) Oracle/Sun introduced a 128-way Sparc processor last week (16 cores with 8 threads each), and you can put 4 of those into a system ... The trend is obvious: Increasing the CPU clockrates is getting more and more difficult, so the engineers start to increase the number of cores. Software has to keep up with the hardware development, and that's especially true for operating systems. FreeBSD and DragonFly BSD have chosen somewhat different routes towards improving SMP scalability, but I think they are both successful. Given the apparent fact that DF seems to achieve similar speed with much lower complexity, I'm even tempted to say that DF is more successful than FreeBSD in this regard ... But I'm a FreeBSD committer, so I'm not allowed to actually say that. ;-) (Just kidding.) Best regards Oliver -- Oliver Fromme, secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing b. M. Handelsregister: Registergericht Muenchen, HRA 74606, Geschäftsfuehrung: secnetix Verwaltungsgesellsch. mbH, Handelsregister: Registergericht Mün- chen, HRB 125758, Geschäftsführer: Maik Bachmann, Olaf Erb, Ralf Gebhart FreeBSD-Dienstleistungen, -Produkte und mehr: http://www.secnetix.de/bsd
