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Linux 2.6.20-rc6 Kernel Performance
Michael writes "The Linux 2.6.20 kernel will feature KVM support, Playstation 3 support, and a variety of other improvements. With the Linux 2.6.20-rc6 kernel out the door, Phoronix has written a performance comparison of the Linux 2.6.20-rc6 kernel against the 2.6.19 and 2.6.19.2 kernels in a variety of benchmarks."
All it takes to get a /. front page link to my ad-word laden website is to create a few bar graphs showing that nothing has changed in the last few kernel revisions and add 2 paragraphs of filler text?
Why is anything in the kernel tree? Jeesh -- why don't you complain about the whole gamut of processors included. Just because it's supported doesn't mean you have to build for that arch. To each his own -- pick the proc(s) you need.
So the bottom line here is that they're almost exactly the same?
In the land of the blind, the one-eyed man is kinky.
Is this a joke?
He's running kernel benchmarks on a laptop?
Looks like half the things he was measuring were I/O bound? On a laptop?
Phoronix.... more like Moronix.
I think that means that it is bootable on a PS3. This kind of thing would only be included if it was compiled for a PS3, and as for "is it required", only if you want to run arbitrary distros on a PS3, which there are people who'd want to do that.
34486853790
Connection too slow for X forwarding? Try "ssh -CX user@host"
Yeah, don't forget why most folks start tinkering with Linux in the first place.
- We love to tinker
- We want closer access to the hardware
- Somebody told us we can't, so that just makes us want to all the more
All three apply to the PS3, as far as I'm concerned!Never ask for directions from a two-headed tourist! -Big Bird
Why is playstation support being included in the kernel?
Why is there x86 support in the kernel? why is there PowerPC support in the kernel?
To make linux run on these systems. Duh.
I tried to read the article, but someone has vandalized it with double underlined words all over the place and annoying popups when your mouse slides over them. I closed the window.
Yeah, that was a totally worthwhile read, no?
Let me give everyone else the bottom line, and save you two or three minutes of your life, that you'll otherwise never get back: Now, back to our regularly scheduled Slashvertising....
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
With the Linux 2.6.19 kernel coming out last November and only two additional releases in the 2.6.19 branch, the Linux 2.6.20 kernel is certainly coming quickly. Linus Torvalds had mentioned in the 2.6.20-rc6 release announcement that this is likely the last release candidate. However, even with this quick kernel release coming the features are definitively impressive. Sony Playstation 3 support and Kernel-based Virtual Machine support are among the exciting features in this release. From today's testing in our environment used and set of benchmarks, there were no definitive performance gains or losses seen throughout the set of tests.
It's nice to get features without sacrificing performance. The added PS3 support would nab those ubuntu people to put it on PS3. Not only that, but yellow dog might get some competition if some peoepl decide to make their own PS3-based distro with all kinds of extras.
In Soviet Russia, dots slash you!
I bought a PS-3 for the sole reason that I want to run Linux on it to use as a cheap, quiet server, and play with the Cell processor, which I think should be pretty fast for DSP and software radio applications.
I'm pretty excited about the Cell, and the Playstation is an incredible value for a small form-factor computer that you can put next to your TV without having fan noise be a bother.
Why not support it in the Linux kernel?
If moderation could change anything, it would be illegal.
It's support for the cell, and some PS3 hardware.
Why would it not be included? If the kernel is still shipping support for 15 year old legacy ISA hardware (yes it is) and Cyrix X86 optimization s(yes it is), it can include support for the PS3, which is likely more in use than either of the above.
There is support for hardware in the kernel that is so obscure that there are probably less than 100 people in the world still using it. There's nothing wrong with this - this is why Open Source beats closed source for overall hardware support - as long as someone is around using it, and someone else maintaining it, there is no reason to remove support for it.
7SPE's are accessible via Linux, as long as you use the Cell BBE SDK..
With a great article title like "Linux 2.6.20-rc6 Kernel Performance", I figured there must be something really notable about this release - and yet, there isn't. Summary: some things a neglible amount faster, some a negligible amount slower. If the "firehose" feature I've seen is anything like a preview of how submitted articles are reviewed for publication, I'd say an important part of this process would be at least a review of the linked content to determine whether or not it satisfies any reasonable criteria of newsworthiness.
Cell as implemented in the PS3 has 8 cells. One is disabled (probably due to poor yields when demanding that all 8 be working.) In Linux, one is devoted to kernel tasks. That leaves you with six Cell SPEs to work with besides the PPC PPE.
Well, yes and no. The real problem is that the SPEs are only good for vector data. Anything else requires that you underutilize them. For instance if you have just two numbers and not a whole matrix to multiply, it takes equally long - you just have one useful result and a bunch of useless results that you didn't want. So certain kinds of tasks will be easier to optimize on the SPEs than others. But in many cases you can probably get good results by just using libraries... for instance if libz and libm were accelerated, that would probably make a big difference. Likewise for widget libraries, sound processing libraries, 3d...
3d brings us to the other point, which is that Linux runs in the PS3 "hypervisor" environment and you do not have unfettered access to the video hardware. I don't know precisely what you're not allowed to do that you can do in the commercial environment though; I've never seen a complete description of that.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Did you only skip to the last page? If you looked over every benchmark, the new kernel had improved performance in almost every test, save for two of the last three.
http://blindscribblings.com - Tasty pop-culture in conceptual fashion.
You misunderstand the Linux kernel ethos. The idea is to include *everything* "in the kernel", but you only have to compile the parts that you want. That way there is a central place to track all changes and maintain compatibility and consistency between all parts of the kernel, without having to set an internal interfaces in stone.
It's not "bloat" if it's only in the source. Simply put, you don't have to include PS3 support in your binary version. In other words, the only way it affects you is a few extra bytes to download when you want to compile it.
This isn't to say that there isn't a lot of good stuff in the kernel, but mostly what these benchmarks show is that nothing affecting these particular tasks got broken.
It's not wasting time, I'm educating myself.
1) A file/subversion server for my home network.
2) It's not, yet. It's arriving today via UPS.
And the main reason I bought it was not as a server, although that's certainly a benefit. I'm more interested in development on the Cell.
If moderation could change anything, it would be illegal.
The hard disk must be PS3-formatted before Linux will see it. Otherwise the hypervisor will not see it and make it available.
BTW:
The hypervisor is a lot like VMWare/Virtual PC/etc. I suspect the Power Processing Elements aren't even fully accessible and that the hypervisor is trapping everything and passing it on as appropriate, like virtualization software you run.
BTW, the virtualization also causes some issues. When I bought a new hard disk for PS3 Linux, it had bad sectors on it (I returned it in the end), but instead of the usual IDE error messages (DriveError) or SCSI errors (with media sense keys), you get nothing, other than a generic "I/O Error reading sector XXXX", which causes the filesystem in use to suddenly go read-only (not sure if ext3 did that or if the hypervisor just disabled the ability to write to the disk - I never had many bad disks with ext3). Basically, you don't even know it's a bad sector as it isn't reported. I suspected it when I could get dd to consistently put the filesystem into read-only mode 16GB in. Another system helped prove the point.
The video hardware is identical - it's virtualized the same way. It's not a driver issue - it's just that Sony has virtualized the video hardware away, and there's no direct access available. Heck, there aren't any WiFi devices accessible either - not for lack of a driver, but that Sony didn't make the WiFi hardware accessible.
Can the creators of this technology choose a better word for it? KVM is already widely known as a KVM switch, Keyboard, Video, Mouse. It lets you connect multiple computers to the same monitor,keyboard and mouse and switch between them.
Choosing the same acronym for this new technology is only bound to cause confusion.
AccountKiller
With that kind of performance increase, my Gentoo laptop is going to be screaming along after the release of 2.6.20.
Ok...was that sarcastic enough? With this crowd, one can never quite know.
I've played with PS3 linux. I can tell you, the hypervisor is just that. It virtualizes the PS3 hardware. ...
I don't know about anybody else, but I find this just conceptually fascinating. Where does the hypervisor run from, anyway? Is it in the machine's ROM, so that there's no way to prevent it from booting? (Without irreversible hardware modifications.)
I was just wondering whether it's possible to get rid of it, and boot Linux on the bare metal, or whether the hypervisor is tied into the hardware so tightly, it's impossible to remove and install a new Domain 0 operating system.
Getting Linux to run on the bare metal, 'below' the hypervisor, will be an interesting exercise in what I suspect may be a large part of the future of "unauthorized" computing. I don't think it'll be long before most consumer systems have something like that in place, so it'll be a good intellectual challenge, if nothing else, to see if it can be gotten around.
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
I also bought a PS3 two weeks ago primarily to develop on the Cell processor. So far, I have written a prototype application that runs 5x faster on the PS3's Cell than on the highest end Woodcrest Xeon at 3.0 GHz. When I am not coding on it, I am also using it as a Blu-ray player. Given all this, plus the fact that the PS3 is a next-gen console (though I don't plan to buy any game), I am probably one of the few to recognize that $500 is dirty cheap for such a polyvant device !
Given that the article, obstensibly about kernel performance, makes no effort to actually cover kernel performance...
I was suckered in; it looked like a worthy topic. Now, I ask myself: Why did I bother?
Just another "Cubible(sic) Joe" 2 17 3061
I take you never worked on PS2 RTE or PS3 Hypervisor? It's not crippled at all, and in fact you can write all the Cell code you want from PS3 Linux. IBM and others provide SDKs and introductory articles on writing and managing SPE code bases. If you want to learn how to do the future of development then you should jump at the chance. We're never going back to single threaded models ever again.
The only current restriction is there isn't accelerated OpenGL from the RSX. You can write an OpenGL ES implementation for Cell and get pretty good performance. I ran OpenGL on top of just the VUs on PS2 RTE and got good enough performance to get my TombRaider reimplementation running at a good framerate for a console. I even had enough memory to fit the PC game paks into memory at the time. My point is so what if you don't have OpenGL provided by RSX. You can still do a software implementation optimized for Cell. You can do a lot more than you think with what is provided so far.
When I see fanboys like you marked 'Insightful' I fear for young teens learning anything. I wonder what you consider 'real development'. This is one of the few ways you can learn streaming / distributed / realtime development techniques on an embedded system at an affordable price. Have you even read any job requirements lately? People already drool over these skills. If you're not a developer then please don't speak about issues you don't even understand. You should be rated 'Funny'.