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DragonFlyBSD 1.2 Released
vsarunas writes "The DragonFlyBSD Team is
pleased to announce
the official release of
DragonFly 1.2.0! Get it
here,
or here,
or as a torrent.
DragonFlyBSD is a continuation of the stable and high-performance FreeBSD
4 branch of FreeBSD with acpica5 and updated drivers so it runs on more
and newer machines. DragonFlyBSD can execute FreeBSD 4 and Linux binaries
and uses the FreeBSD ports collection. In addition, DragonFlyBSD is also
officially supported by pkgsrc. This release represents a significant milestone in efforts to improve
the kernel infrastructure. It features a standards-conformant
SACK implementation, improvements to the VFS layer, and a multithreaded
networking stack that utilizes the DragonFly lightweight message
passing system to communicate among processors. More information can
be found on Matt Dillon's journal and the
Status page
of the DragonFly wiki."
Fly Fred Fly!!!!
I would be interested in hearing from people how either of these BSD alternatives stack up as a desktop box.
If I wanted to install a BSD on my little home router/gateway, just for the sake of playing around with BSD, which BSD is the one to cut your teeth on?
With linux, the choice of distro is pretty much irrelevant - to me at least - because I wind up with virtually the same system, the only differences being the layout of some rc scripts.
The world of BSD isn't the same though, so which is the most prolific, or newbie-friendly, or has the widest support for common hardware, etc?
About the only thing keeping me from playing with BSD is the lack of a single "entry point".
I don't need no instructions to know how to rock!!!!
for the performance differential between DragonFly and the regular FreeBSDs ?
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
It outlived the Pope.
I don't know what the heck you've been reading, but performance has never been one of OpenBSD's strong points as compared to Linux and the various other BSD's.
Free will is just an illusion
FreeBSD has not been the best FreeBSD release but it's *not* dead. 5.3 has been the *first* stable release of the 5.x series, and as expected is not as polished as it should be
I read the mailing lists (I'm not a FreeBSD user tough), and lots of work is happening. All those benchmarks you've seen where freebsd 5.3 loses were done with the 5.3 code which didn't incorported lots of performance work, just to get a stable 5.3 release
Expect 5.4 to be the real 5.x release ie: fast (LOTS of performance work is happening in the threading and VFS land) and stable (lots of critical bugs has been fixed, 5.3 was the first public release)
And no, FreeBSD 5 is not dying. RIght now FreeBSD is the BSD with better SMP support (and getting better), and dual core CPUs are starting to be sold this quarter. NetBSD and OpenBSD are not even near of the SMP support Freebsd has (oth of them detect several CPUs, but it will take all the year s it took to freebsd 5.x to use them efficiently, and most of the benchmarks done against NetBSD/OpenBSD are with only one CPU, which doesn't measure all the work done in the 5.x branch.
It was my impression that one of the reasons for FreeBSD-5.x was to rearchitecture several parts of the kernel for better SMP support. I know, I know, there were problems but it seems that it had to be done, and the sooner the better.
Now, if DragonFlyBSD continues down the road that was set by the 4.x train, what is going to be done about multiprocessor systems? I mean, multicore processors are right around the corner and other OS's (besides the BSD's I mean) like Linux are getting better and better(I won't even bother to mention Solaris).
I do not profess to be some kind of expert, anyone has anything informative to say about DragonFly's plans on this?
It outlived the Pope.
Are you sure he's dead? Has Netcraft confirmed it?
Treehugger? Treehugger... Treehugger!
I was excited when I heard a while ago about a new BSD variant because there are areas where BSD isn't specifically tuned to. However, Dragonfly BSD doesn't seem to address any particular deficit of the other BSDs. Every other BSD split has had a mission, OpenBSD to concentrate on security and NetBSD to concentrate on remaining cross-platform portability. What exactly is the reason for Dragonfly BSD?
I certainly don't see any kind of "mass disillusionment". FreeBSD 5.x has brought about added complexity for the sake of performance, namely in the SMP and multithreading arenas. These are areas where you will find the performance of NetBSD rather lacking. While NetBSD may win at certain meaningless microbenchmarks, the real world performance of FreeBSD, especially on multiprocessor systems, will generally be quite better. NetBSD has always had its primary focus on portability, whereas FreeBSD's has been primarily on performance. Microbenchmarks indicate, if anything, that FreeBSD has chosen higher overhead implementations which increase overall performance, whereas NetBSD has implementations whose simplicity incurs lower overhead on microbenchmarks.
Firefly has taken a radically different approach and is attempting to refactor a BSD kernel into a more microkernel-like operating system. So while FreeBSD decided to take the SunOS/Solaris-like approach, DragonFly has gone the way of Mach. This is a rather fundamental design schism, and is more indicative that microkernel concepts are still quite valid than any kind of mass disillusionment over FreeBSD 5.x. I think it's great that they're introducing microkernel concepts to a stable and mature POSIX compatible OS rather than starting from scratch, but sadly I think DragonFly will be an OS that has trouble finding its niche.
FreeBSD is the most polished and user-friendly BSD for your x86 box, by far.
..features a standards-conformant SACK implementation..
DragonFlyBSD: The BSD with Balls
This is my personal opinion, the biggest problem I had with other BSDs was the way they didn't fit with the way I prefer to do things. People with different preferences can easily have similar needs and come to different conclusions.
OpenBSD's goal is security, but as a side effect it's very easy to set up (eg hard to screw up and have an insecure configuration), and there are very few bugs compared to FreeBSD.
You don't tweak the kernel because the default one has almost everything that is supported. It makes the kernel bigger than it might otherwise need to be, but if you've got more than 16 mb of memory it doesn't matter.
There is a performance disadvantage (although PF performs well, and that's usually the only thing that matters), but things are easier to set up most of the time. If it's just a home gateway/router, your computer is probably bigtime overkill anyway, so you don't notice the performance disadvantage and you do notice the ease of configuration.
I probably wouldn't use it as a desktop OS because of the lack of software, but all the BSDs suffer from this. I couldn't even get by with FreeBSD as a desktop due to the lack of software. As a router, I haven't had any problems with getting software. What isn't in ports generally compiles fine. The one thing I haven't been able to get working with OpenBSD is a Haskell compiler, and the Haskell interpreter works fine so I don't care that much...
I rarely criticize things I don't care about.
Well, I have to say the slashdot response to this release is a marked improvement over the response to the last release. Most people are actually getting the concepts right this time! Kudos!
There are a few things I will clarify about the release, in particular about our approach to SMP and the inevitable comparisons against, FreeBSD.
On the SMP front what we are doing is basically rearchitecting big chunks of the kernel to operate efficiently in both UP and SMP environments, to be NUMA-friendly, and to be as maintainable as possible. Rather then throw mutexes around existing code we are undertaking a huge effort to make as many of our subsystems as mutex-free as possible by localizing the subsystem's operation on a per-cpu basis. Most of the time that means rewriting them from scratch.
One example of this is our core Light Weight Kernel Thread scheduler (LWKT). Each cpu has its own indepenant LWKT scheduler which means that any given copy of the scheduler itself does not have to deal with or worry about contention between cpus. The code is very, very clean. If you think about it a bit you will realize that such a beast would work just as efficiently in an SMP environment as it would in a UP environment, and that is indeed one of our major goals.
A second example of this is our network protocol stack (whos major architect is Jeffrey Hsu). A TCP connection goes through a hash and is routed to a tcp protocol handling thread on a particular cpu. If you have N cpus then your TCP connections will generally be split about evenly between the cpus. Any given connection is localized to its cpu which means that all the work related to that connection occurs on a single cpu and thus does not have to worry about or deal with contention between cpus... and operates as efficiently on a UP system as on a SMP system. The L1/L2 cache effects are an important bonus as well but the winning ticket is the ability for the protocol threads to run in a tight loop without needing to obtain or release a single mutex, lock, or other synchronizing mechanism other then the occassional critical section (which is a cpu-localize synchronization mechanism against interrupts).
Another major goal is to make the code more maintainable... readable, understandable, etc, without any major gotchas to an unwary programmer, especially new programmers who are attracted to the project. This does not mean that FreeBSD is less stable, but I certainly believe that DragonFly's code base is a lot easier to maintain and a lot easier for new programmers to work with, with a much shorter ramp-up time then someone trying to dig into the FreeBSD codebase and far fewer new bugs introduced. I am taking a long-term view here.
The problem with building an SMP friendly algorithm which requires a lot of synchronization to avoid contention (the mutex model) is that it is really easy to make a mistake and introduce a hard-to-find bug, especially if you are just ramping up on the codebase. The solution is to use algorithms (aka cpu-localization algorithms) that avoid the contention in the first place, and that is what we are doing. Regardless of FreeBSD's current stability (and I believe that FreeBSD is now far more stable then it was a year ago), they had to go and stomp hundreds of bugs introduced by experienced programmers. That's a red flag in my book, one that I am making a major effort to avoid in the DragonFly codebase.
In less then two years of work (with very little destabilization of the kernel during that period, by the way), we are now within shouting distance of FreeBSD's and Linux's SMP parallelism. The only area where we are still significantly behind is in boot-time interrupt routing. This release is the last release where the Big Giant Lock is going to be in the critical path. We spent a lot of time isolating subsystems in order to reach this point, to be able to now take the last few steps and actually turn the Big Giant Lock *off* on a thread by thread basis. Not only tha