Slashdot Mirror
ULE Now The Default Scheduler On FreeBSD
Dan writes "FreeBSD's Jeff Roberson says that the ULE scheduler has entered into its probationary period as the default scheduler on FreeBSD. He says that if all goes well, it will remain the default through the rest of FreeBSD 5.* releases. He is requesting you to switch over and test it. The ULE scheduler was designed to address the growing needs of FreeBSD on SMP/SMT platforms and under heavy workloads. It supports CPU affinity and has constant execution time regardless of the number of threads."
This is great news. The O(1) scheduler in Linux is awesome, and it's good to see FreeBSD keeping up. Now if we just had an O(1) way to squash *BSD trolls, Slashdot would be saved.
In Soviet America the banks rob you!
GNU/KFreeBSD is a project that doesn't get enough press.
Most GNU systems use Linux as their kernel, but this doesn't have to be the case. The porting of GNU to the FreeBSD kernel is almost complete. (the project name changed from GNU/FreeBSD to GNU/KFreeBSD after a trademark discussion with some FreeBSD folks.)
FreeBSD people say that their kernel is rock solid, has the best uptimes, most robust networking, and now it's getting an improved scheduler. So it would make sense for GNU users to considering using the FreeBSD kernel instead of Linux.
Having everyone using the same kernel just makes life easier for worm writers, and corporate attacks such as the SCO fiasco.
Of course, adoption will be hampered by the marketing mistake of calling the whole OS "Linux", but I hope that choice of kernels will become more normal in the future. It would also help if they came up with a friendlier name than "GNU/KFreeBSD" (8 sylabyls!).
Anyway, I hope to start using the FreeBSD kernel soon.
Expert in software patents or patent law? Contribute to the ESP wiki!
I uise freeBSD everyday, and I have to ask why you would care about GNU/freeBSD. The utilities are essentially equivelent. There is a little more bloat (read features) in some of the GNU stuff. Nothing really significant though.
Sure it is neat that they can do it. However to say everyone should want to run it? I don't get it.
1. is the most SMP scalable (parallel)
Long term or short term? Linux is faster now but the BSD folks always seem to spend a lot more time actually researching the issue.
2. is the most algorithmically scalable
I don't even know what this means. Are you referring to the scheduler and other system processes? Linux has an O(1) scheduler - only it ran head first into a brick wall in certain instances. FreeBSD spent a _lot_ of time implenting a robust and stable scheduler and it shows. NetBSD looked at the Linux algorithmns and tied or beat them in every case.
3. has fastest single threaded performance
How about which OS is more stable? How about which OS didn't have an idiotic 2TB block device limit for years longer than the BSD's? How about which OS didn't have a 2GB file size limit?
4. runs on more architectures
Can you say NetBSD? Besides which, the only computers I own are DEC Alphas and x86 boxes. I could cares less which OS runs on the DreamCast.
5. supports the most hardware
How about which one supports the hardware you actually want to run on, and not the toaster in your basement.
6. has the fastest TCP/IP stack
For what application? You ask this question as if there is one TCP stack that is fastest in all applications. You also probably prefer a fast stack to a stable one.
Answers won't be accepted without evidence.
Questions won't be accepted from AC's. Besides, if you want answers, go look them up yourself.
-sirket
Now it all makes sense... CHEESE GRATERS.
So that's why I'm having trouble scaling on my Quad Xeon.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
Security updates are still released for older FreeBSD versions, as well as NetBSD versions. Have a look at http://www.netbsd.org/Security/ and you will see that security updates are made for NetBSD 1.5. NetBSD 1.5 was released at the end of 2000, yep, that is over three years ago. It is true that the FreeBSD EOL is shorter, but it is not hard to track a -STABLE branch.
OK you got 1 of 6 correct. You fail.
Linux and FreeBSD kernels, which
1. is the most SMP scalable (parallel)
Linux. (Linux and FreeBSD both started with a BKL about 5 years ago. Linux is now being used on 512 processor machines, FreeBSD doesn't scale past 4 CPUs for all their research).
2. is the most algorithmically scalable
Linux
3. has fastest single threaded performance
Linux (from the horse's proverbial mouth).
4. runs on more architectures
Linux. See here and here (The Linux Kernel supports more architectures than the NetBSD kernel, idiot).
5. supports the most hardware
Linux. See here and here (NetBSD is actually the one that prides themselves as running on toasters. And nobody cares about your shitty DEC Alphas. IA64, POWER are where its at now).
6. has the fastest TCP/IP stack
Linux
See you again next year.
They actually used Linux's scheduler. Then they go and claim Linux rips off heaps of their code. What a joke.
What are you talking about? Linux use to use the BSD TCP stack verbatim. Moreover, SCHED_ULE has nothing in common with any of the Linux schedulers.
-sirket
How about which OS supports more mainstream hardware, offers better commercial support, and whose releases aren't EOLed after 12 months a la FreeBSD? Gimme Debian's two years (or RHEL's five years) any day. Maybe you have time to upgrade all your boxes every 12 months; personally I prefer to USE my systems rather than fiddle with them.
If you ever tracked -RELEASE or -STABLE you would know what a trivial joke it is to keep a FreeBSD box current. The system is so tightly integrated that I could set up automated upgrades and not even worry about them. Not that I would expect a Linux user to understand this.
What kills me about Linux users is you think that us BSD users don't run Linux. I run more Linux boxes than you can possibly imagine. Sadly most of them are RedHat. Even the Debian ones, however, aren't as clean to administer as my FreeBSD boxes.
-sirket
Gosh, BSD has been around for how long and it took Linux to get them OTA's to do a proper scheduler. Then they claim they are better. What a joke. No wonder I won't use BSD.
The BSD scheduler was rock solid and damned reliable. Upgrading a scheduler is not something one jumps into head first. It is a lot like all the major differences between Linux and BSD. The Linux folks jump right in and code stuff. The BSD folks think about the problem, theorize and evaluate possible solutions, then code.
It is a lot like with the file systems. Linux has 3 journaled file systems while FreeBSD skipped them all and implemented softupdates.
-sirket
The Linux 2.4 kernel (2.4.20 was the last time I did an install where I ran into this problem), which is still the stock kernel, has 2 TB block device limit and -STABLE does not. Look it up.
As for a minor issue? Jesus christ. I have run into it so many times my head hurts. If you don't run file systems larger than 2TB than we have nothing to discuss because we are clearly in different ends of the business.
-sirket
2. is the most algorithmically scalable
This is an old study that was already addressed by the NetBSD folks whereby they beat Linux in almost every test.
(The Linux Kernel supports more architectures than the NetBSD kernel, idiot).
I love any argument that falls into random name calling, moron. As for architectures, go ahead and list them.
And nobody cares about your shitty DEC Alphas.
Jealous?
IA64, POWER are where its at now).
Why isn't google running on IA64's or POWER processors then? Because for most applications, 5 PC's are a better bargain than 1 POWER based system. As for IA64, as you already pointed out, FreeBSD runs on it.
has the fastest TCP/IP stack
I like how you link to a discussion about a particular driver as an example of which TCP stack is faster.
-sirket
You should be a politician. Pick issues where your candidate is ahead and pretend the other issues do not exist. I like that.
As a side note, who had USB support first?
-sirket
"you would know what a trivial joke it is to keep a FreeBSD box current. "
In theory. In practice I was always getting ftp timeouts and other obscure errors whatever site I tried to connect to. This was with 4.6, maybe
things have changed since then but I got so fed up with it I gave up. So please , give the "BSD is so easy to maintain" spiel a rest. It isn't always the case.
According to this, Con Kolivas suggests that the ULE scheduler is prone to the same problems that the Linux O(1) scheduler faced initially. Can someone with a more detailed knowledge of the workings of the ULE scheduler throw some light on this?
If you did not post as AC, we might take you somewhat seriously.
Ignoring the comment implying "obvious" superiority of softupdates, I'd like to point out that at least two of the journaling file systems available for Linux (JFS and XFS) come from companies with as much experience designing and writing FS code as anyone. To suggest that there is no direction or planning for code that goes into Linux (filesystems or otherwise) is pretty close-minded and bordering on ignorance, regardless of your preferences in software development strategies.
if your worried about usb support you aren't using Linux or BSD for its strongest application which is server. USB support only maters for desktop usage.
I've never had an problems connecting to ftp.kernel.org to get the latest version of the linux kernel but then thats using bog standard ftp, not some
lash up semi-automated system a la BSD.
USB support only maters for desktop usage.
Unless of course you want a keyboard or mouse, and the ones laying around happen to be of the USB variety. Hot-pluggable keyboards are quite handy for servers.
Don't blame me, I didn't vote for either of them!
That is true.
Hot-pluggable keyboards are quite handy for servers.
WTF are you talking about? You unplug things from your servers? Hot-pluggable keyboards are useless for servers, because your business is either big enough to have a KVM switch on your servers (preferably a nice pull out rack-mounted LCD), or small enough to be able to afford 5 minutes of downtime while you swap keyboards.
As a side note, you could buy a new PS/2 keyboard and mouse for less than $10, or buy the adapters to convert them from USB to PS/2.
--That's the point of being root, you can do anything you want, even if it's stupid.
WTF are you talking about?
I've got a rack of twenty servers. None of them have monitors or keyboards. If you need physical access to them (and ssh won't do), you hook up a monitor and keyboard to them. A KVM switch that handles twenty servers is going to be much more expensive than the monitor and keyboard, so you want a better solution.
In the past, the solution was the serial port. I connect my Wyse terminal the serial port and I'm set. That's because the serial port is hot-pluggable. But too many people are lobbying to get rid of serial ports. Enter USB.
Don't blame me, I didn't vote for either of them!
Its true. Another good example would be the PowerPC CHRP and PReP platforms (IBM RS/6000), which are not by any stretch a Macintosh.
I have had very little luck getting a Linux kernel to boot on my RS/6K (a CHRP platform RS/6K), only getting some really old Yellow Dog Champion Server kernel (2.2.14 i think) to load a few kernel messages very fast then panic because the scsi system that my hard disk was on wasn't supported...
On the other hand, I wouldn't want to run NetBSD on it because of the lack of decent SMP support.
Ended up just saying to hell with it and putting a proper copy of AIX on it. Its a great server now... Go Unix!
.