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Linux Kernel 2.6.21 Released
diegocgteleline.es writes "Linus Torvalds has released Linux 2.6.21 after months of development. This release improves the virtualization with VMI, a paravirtualization interface that will be used by Vmware. KVM does get initial paravirtualization support along with live migration and host suspend/resume support. 2.6.21 also gets a tickless idle loop mechanism called 'Dynticks', built in top of 'clockevents', another feature that unifies the timer handling and brings true high-resolution timers. Other features are: bigger kernel parameter-line, support for the PA SEMI PWRficient CPU and for the Cell-based 'celleb' Toshiba architecture, NFS IPv6 support, IPv4 IPv6 IPSEC tunneling, UFS2 write, kprobes for PPC32, kexec and oprofile for ARM, public key encryption for ecryptfs, Fcrypt and Camilla cipher algorithms, NAT port randomization, audit lockdown mode, some new drivers and many other small improvements."
And I just upgraded to 2.6.20-15! (Kubuntu Feisty Fawn)
"We may face a scorched and lifeless earth, but they're accountable to their shareholders first."
Is it just me, or are all these options that are added with every new release going to result in a bloated kernel? It seems like every release adds new stuff, but I never see anything outdated taken away.
Yes, I know that you can recompile and remove what you don't need, but most "non-uber-geek" users are not going to be able to handle that, and most distros are going to include a kernel with the kitchen sink compiled in.
There is no "I disagree" mod for a reason. Flamebait, Troll, and Overrated are not substitutes.
I haven't been able to get anything past 2.6.17 to boot successfully, I think they seriously hosed the ATA shit.
Speaking of KVM (slightly offtopic, but not totally) are there any worthwhile management utilities for it yet? I actually ended up giving up for a while on KVM entirely because the video device is horribly slow and VDE support is not reliable, and I'm using vmware server, but I did have to give it a try. I'd love to use KVM (since I have supported hardware and it's Free software, and I'd love to minimize my use of the closed stuff) but beyond those problems (which will hopefully both be fixed relatively soon) there is simply no decent management software unless you're on redhate. Either virt-manager or libvirt is badly broken and won't work properly otherwise. UNLESS... has anyone out there gotten it working on debian/Ubuntu yet? I tried for a while, but I'm just not a good enough programmer and the programs ain't done yet.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
I follow prerelease kernels and I've been waiting for this. I've found that running my VMWare hosts and guests with tickless, low-HZ, voluntary-preempted kernels is seriously reducing the overhead you get when you run more virtual CPUs than real ones in your box.
I can't wait for it to mature on PPC, MIPS, and x86_64! Right now it's 32-bit x86 only.
"Sometimes, I think Trent just needs a cup of hot chocolate and a blankie." -Tori Amos on Nine Inch Nails
... but does it run Linux?
Once again, it took many months of work to optimize an idle loop.
Here.
Must be Linus!
but I wonder if we're ever going to see 2.8 at this rate. The current kernel revision is MILES away in technology from 2.6.0. What will it take to move to 2.8, or (dare I say it?) 3.0? What qualifies as a major enough change?
+++ATH0
Glad to hear that it's been published. Where can I download the PDF? I heard that Darl dies near the end, but I want to read it for myself.
Stop it. This isn't the GameFAQs forum, and nobody cares if they're the first post here. If you don't have anything to contribute, then don't post.
On topic:
All of this built-in virtualization stuff sounds great. How long, on average, does it take the Ubuntu repositories to receive new kernels?
You're confusing Linux with this Windows 95/98. However, this problem or this another problem are even more funnier
-- In the beginning was the WORD, and the WORD was UNSIGNED, and the main(){} was without form and void...
As an owner of a Macbook Pro, I've been waiting for this to get released. The Dynticks integration will (hopefully) help lower power consumption and heat output. Though this will help reduce heat and power on all platforms, those running Linux on a MBP C2D know it's hard to keep the fans from spinning up from relatively little activity.
:)
Next up is to get ATI to actually support any power saving features in fglrx on the MBP C2D and give the mAdWiFi guys more time to work out the features on the Atheros AR5008.
OSX, right now, still has a significant advantage in keeping heat and power consumption down. Even though, I imagine some will testify that even OSX is having a hard time with it...
Here's to testing out 2.6.21 tonight
It's me who sent the headline. "Publicar" (to publish) is what people usually uses for those cases in spanish. So there you've the answer for your question :)
(I also planned to add the number of months of development (almost 3, 80 days), but I forgot it)
That's cool, but is this really news that's Slashdot-worthy? Sites like LWN and KernelTrap have already reported this, and anyone who's interested in Linux development is pretty much guaranteed to follow the former at least, I think (and most likely the latter as well).
butter the donkey
"-1 Troll" is the apparently the same as "-1 I disagree with you."
It doesn't and never did. However, the uptime clock wraps around after 497 days. Took me two hours of finding out why the box rebooted (and then why there was no indication of the reboot in the logs) one day to research that. That same box has since looped the clock a second time. So I can say for sure it stays up for more than 50 days. :-)
Assorted stuff I do sometimes: Lemuria.org
As far as I know, Linux never had a 49.7 day problem, but it did have a problem at 497 days. I have a machine at home running the 2.4.20 kernel and every 497 days my uptime restarts, but it hasn't crashed. It's gone through 2 rollovers so far and has been up for over 3.72 years. It will hit its next rollover around September. I really need to build a new server... I just don't know if it will be as reliable as this one has been.
This post is encrypted twice with ROT-13. Documenting or attempting to crack this encryption is illegal.
497 day wrap around? You should switch to Windows. I'm sure no such problem has ever been reported on that OS.
Slow down, cowboy! It has been 4 hours since you last posted. You must wait another few hours.
The public key support for eCryptfs can handle more than just public keys. It includes a communication mechanism with a user daemon that can be queried from the kernel on file open events. There is a pluggable key module interface accessible through that daemon. OpenSSL is currently implemented, but there is nothing stopping anyone from writing a module to use GnuPG or any other key management/encryption backend, all in userspace. The module just needs to accept a key signature, and it can perform encryption and decryption based on whatever that signature refers to.
? id=218556
In other news, eCryptfs has recently been given the go-ahead for inclusion into Fedora:
https://bugzilla.redhat.com/bugzilla/show_bug.cgi
In the meantime, you can grab all the userspace stuff from the eCryptfs SourceForge site:
http://ecryptfs.sourceforge.net/
An unjust law is no law at all. - St. Augustine
I know that's you, Ballmer. Anonymous, my ass!
Remember the future...
This means your CPU is much more powerful than what you really need. I used FreeBSD a bit in the 1990s, but switched to Linux because the kernel allowed me better fine tuning in the 486 CPU I had at the time.
Today the CPU is way over my needs too, but I stick to Linux because, first, I have no need to switch and, second, Linux has better hardware support than the others you mentioned.
6 digit (l)user :P
It doesn't work that way outside of x86-land. As another responder said, the PWRficient isn't just a CPU, it's a SoC (System on Chip). To compare to an x86 system, that would be like having a low-power CPU, north bridge, south bridge, SATA controller, ethernet controller (but not PHY), memory controller, I2C interface, USB controller, interrupt controller, etc. all wrapped up on one chip. This is quite common in the embedded world, where most PPCs are used these days (I'm working on one myself in my day job).
Since each SoC is totally different, except maybe for the CPU core, porting Linux (or any OS) to it is a little more difficult than just compiling it and loading it. Check out the arch/ppc or arch/arm directories for examples of all the different chips supported. While the work certainly isn't comparable to, say, porting Linux to an entirely different CPU architecture, it does require several new files with custom code to support things like the way interrupts are assigned to the specific functions on the SoC.
Worse, sometimes new drivers need to be written for certain on-chip peripherals, because some bonehead empire-building managers at the chipmaker wanted to justify a higher budget for their department by, instead of just re-using an existing USB controller or Ethernet controller design and plopping that onto the chip, putting together a whole team and spending months creating a new controller because it might improve performance by a whopping 5%. My last company, which made a lot of ARM-based chips, was especially guilty of this.
But apart from virtualization with VMI, paravirtualization, live migration and host suspend/resume supportsupport for kvm, a tickless idle loop mechanism with unified high resolution timer handling, bigger kernel parameter-lines, support for the PA SEMI PWRficient CPU and for the Cell-based 'celleb' Toshiba architecture, NFS IPv6 support, IPv4 IPv6 IPSEC tunneling, UFS2 write, kprobes for PPC32, kexec and oprofile for ARM, public key encryption for ecryptfs, Fcrypt and Camilla cipher algorithms, NAT port randomization, audit lockdown mode, some new drivers and many other small improvements, what has Linus ever done for us?
At least they didn't publish it to Google, or it would be gone.
does not an arbiter of a versioning system make. :p
More things have changed between 2.6.0 and 2.6.21 than changed between 2.0 and 2.2.
How's that?
+++ATH0
Linux has amazing hibernation support. I use some software called Suspend2 on my laptop, and it works like a charm. It was a little difficult to get it going the first time, but now that it's installed I find it very fast and reliable. It doesn't even require any special support from the hardware!
Never eat more than you can lift -- Miss Piggy
It wraps after 49.7 days on kernels with a faster tick rate than yours.
Just tried the latest kernel and it hangs on trying to fire up the second ATA instance. Not even a kernel oops, nothing. That's true whether I use the vanilla kernel or Red Hat's RPM. Something is screwed up, and from the sounds of it, there's more than one of us experiencing a failure at the same point, so that would be the obvious suspect.
This problem needs to go to lkml, and cc Andrew.
Have you got your LWN subscription yet?
A tickless kernel gives the scheduler much finer control, and down the line will probably improve performance.
http://lwn.net/Articles/223185
As I said, it is running 2.4.20. The rollover problem was fixed in 2.4.21 so 2.6 should not have this issue.
This post is encrypted twice with ROT-13. Documenting or attempting to crack this encryption is illegal.
Note, that it's "to release" in English. :)