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From the Mailing list archives
The ACPI AML interpreter (i.e. code in directories under drivers/acpi, but
not source in drivers/acpi directly) has been released by us (Intel) under
the GPL. It has also been released separately under a looser license, so
that other OS vendors may make use of it.

(same anon coward here)

I think you've missed the point.

Ooops. You're right, I have. Kevin Lawton even explained it in the lkml post I quoted:

plex86 can bolt on to bochs for accelerating user code, reverting back to bochs for emulation of kernel code - perhaps good for running non-Linux

There's another huge win here! Kevin has proven that you can run a high-speed Linux kernel in a VM sandbox WITHOUT ANY EMULATION. This is news in itself. The flood-gates are open now for massively virtualised boxes. Kevin is talking about writing special Linux drivers which don't speak to real hardware but instead communicate with the plex86 "host". This means we could soon have 100s of Linuxes running on a single platform, ala IBM's S/390.

Well, is this really such a huge win? We already have UML which does Linux virtualisation and by its nature already has the "special Linux drivers which don't speak to real (or emulated) hardware but instead communicate with the [...] host" optimisation and also isn't x86 specific. What things does Linux-on-plex86-on-Linux do better than UML?

This patch doesn't hurt performance. In fact, it does absolutely nothing to a normal kernel. It's only activated by an option at compile time, to build a special kernel for the "Hardware Abstraction Layer", which won't even run on bare hardware.

Here is a link to the actual patch.

Yes, it IS interesting; and no, it won't be confined to Linux hosts. (Nor guests, ultimately -- at the least, *BSD will be available.) I do agree that in a sense it looks like "giving up", though; it's certainly become less ambitious.

Arrggh, it's too hard.

I work for VMware. if you want to believe we've corrupted Kevin's precious bodily fluids, feel free. I don't speak for the company, and I know nothing beyond what slashdot has posted about plex86. Consider yourself disclaimed.

If I understand the story correctly, plex86 has basically surrendered. They've given up on running arbitrary supervisor level code; the Linux guests that Kevin refers to above require a patch to "fix" something the new "lean, mean" plex86 gets wrong.

If Linus is feeling even vaguely himself, he will not accept this patch. Ordinarily, people trying to put stuff into the kernel that a) hurts performance, and b) fixes no real problem, but c) is critical to some contrived project that seems really important to the contributor get entertainingly flamed, and then shown the door. In fact, Kevin's most likely motivation for submitting this as a Slashdot story is to marshall support for his Linux patch.

Even if Linus does accept this patch, I can guarantee you that Microsoft, the FreeBSD team, the now non-existent Be, etc., won't all be taking helpful hints from Kevin about which x86 features they may and may not use. Ergo, there is nothing interesting (either commercially or geekily) you can do with plex86; the most it can hope for is to run recent-ish Linux guests on recent-ish Linux hosts. Bestill my heart.

On the upside, maybe Kevin will stop implying that VMware stole Bochs, now that he's spent four years trying to clone our software and has finally admitted defeat.

if Free solutions like Plex86 took off, it would destroy VMWare's business model

Well, there's no chance of that here. What this announcement means is that plex86 can only provide a virtual user mode x86 - i.e. it cannot virtualise an OS and give you Windows on Linux, for example.

Frankly virtual user mode seems pretty pointless to me. Kevin Lawton thinks it is useful because you can modify Linux (and other OSes where you have source access) to be a user mode task and then get Linux on Linux using the new plex86.

So, it's a competitor for User-Mode Linux and the like, and not a competitor for VMWare.

To be honest I don't know how well it compares against UML, but Kevin Lawton seems to have come at this from the route of "gosh, virtualised ring 0 x86 is Really Hard - lets abandon that original objective and do something similar but easier" (see for example this LKML post) rather than "what's the best way to do Linux on Linux".

I don't know about the other problems; if you submit them to our Bugzilla with a more detailed explanation we would be happy to help.

...can be found here.

I've been looking for this type of device too. If anyone who has actually done this could post a detailed HOWTO, I would really appreciate it.

I did this, and I found this howto extremely helpful. I made some simple changes to their scripts (lame parameters mainly), but this should give you what you need:

Linux Radio Timeshift HOWTO:
http://osl.iu.edu/~tveldhui/radio/

I think he intended for the question to be "how does the O(1) work?", and not "what's O(1)?". The article mentionned the two priority queues but nothing more.

There's a nice description about how it works here:
http://www.uwsg.iu.edu/hypermail/linux/kernel/0201 .0/0810.html
Just scroll down to the "Design" section (quarter of the way down the page).

Thanks, I see that now. Works better for some (most?) ppl, and some can't boot. Standard crapshoot scenario, I suppose I'll try it and see, coz I really want software suspend, which I had working when the dead HD was alive. More so than sonypi.

Link for posterity

It seems to be

why aren't more using it??

It's proprietary software. A better question is "Why doesn't Intel dedicate engineers to optimizing gcc's code generation for ia32 and ia64?". This would be a much more useful contribution.

~Phillip

There are lots of legal issues. See lkml for some recent commentary by Linus on his interpretation, as of two weeks ago, on the legality of non-GPLed modules.

You can follow what's going one without filling up your inbox here.

This is wrong -- Chris Hellwig wants him banned from LKML. Alan Cox, Roman Zippel, Adam Richter, Jeff Garzik, Andrew Morton, and Larry McVoy want not to have him banned (for reasons of free speech and the efficacy of killfiles for those who don't want to hear him), and so far no one's piped up agreeing with Hellwig. It would be correct to say that "a kernel developer" wants to have him banned.

This is wrong -- Chris Hellwig wants him banned from LKML. Alan Cox, Roman Zippel, Adam Richter, Jeff Garzik, Andrew Morton, and Larry McVoy want not to have him banned (for reasons of free speech and the efficacy of killfiles for those who don't want to hear him), and so far no one's piped up agreeing with Hellwig. It would be correct to say that "a kernel developer" wants to have him banned.

This is wrong -- Chris Hellwig wants him banned from LKML. Alan Cox, Roman Zippel, Adam Richter, Jeff Garzik, Andrew Morton, and Larry McVoy want not to have him banned (for reasons of free speech and the efficacy of killfiles for those who don't want to hear him), and so far no one's piped up agreeing with Hellwig. It would be correct to say that "a kernel developer" wants to have him banned.

This is wrong -- Chris Hellwig wants him banned from LKML. Alan Cox, Roman Zippel, Adam Richter, Jeff Garzik, Andrew Morton, and Larry McVoy want not to have him banned (for reasons of free speech and the efficacy of killfiles for those who don't want to hear him), and so far no one's piped up agreeing with Hellwig. It would be correct to say that "a kernel developer" wants to have him banned.

This is wrong -- Chris Hellwig wants him banned from LKML. Alan Cox, Roman Zippel, Adam Richter, Jeff Garzik, Andrew Morton, and Larry McVoy want not to have him banned (for reasons of free speech and the efficacy of killfiles for those who don't want to hear him), and so far no one's piped up agreeing with Hellwig. It would be correct to say that "a kernel developer" wants to have him banned.

This is wrong -- Chris Hellwig wants him banned from LKML. Alan Cox, Roman Zippel, Adam Richter, Jeff Garzik, Andrew Morton, and Larry McVoy want not to have him banned (for reasons of free speech and the efficacy of killfiles for those who don't want to hear him), and so far no one's piped up agreeing with Hellwig. It would be correct to say that "a kernel developer" wants to have him banned.

I've been reading the list and well..
This is about 1 of 3 different posts talking about 'what needs to be shown to linus when he gets back'

This is also the very first post of this one thread specific.. theres been about 5 or 6 more major things added to the list that people are hoping to get in ... Linus essentially said he wasn't leaving anyone in charge so they're trying to get one main list to give to linus (with links where possible) so that he can quickly go threw everything when he gets back

Also.. it seems noone on the list is sure whether this will be 3.0 or 2.6 at least noones given any real definate answer as far as I could see..

the lastest version of this list is here.. which compiles all the other threads in one.. is here

Reportedly, that error message is traditional, and used to be accurate. You'd get that if the printer had jammed in such a way that there was paper pressed on one side against a spinning part, generating heat and paper dust. By the time you got to the printer, it would probably have burst into flames. Of course, the printer could have broken in a less catastrophic way, but people don't tend to complain when their computer tells them their huge printer is on fire and it turns out it's merely broken. These days, of course, printers rarely burst into flames, but if there's something mysteriously wrong with the printer that's not one of the standard problems, who knows? (The message tends to come up if the kernel doesn't understand the printer status quite right)

See this linux kernel post.

The only benefit of increasing HZ is latency.

Presumably you meant "The only benefit of increasing HZ is decreasing latency" which is not a bad thing unto itself. Most people run interactive desktop applications, not scientific number crunching jobs for days at a time.

Having a minimum granularity of 1/50th of a second for a select() when HZ=100 really sucks, quite frankly.
Music players and animation programs have to resort to busy wait loops to get good response and tie up all CPU in the process. This is completely unnecessary in a modern OS.
It's 1/50th not 1/100th of a second with HZ=100 because of the way POSIX defines select() you have to wait for two jiffies at a minimum according to Linus.

Anyway, HZ > 500 sure as hell is better than HZ=100.
A HZ-less kernel with on-demand timer scheduling would be much better, though. IBM has such a kernel patch for their mainframe version of Linux to improve responsiveness when hundreds of Linux VMs are running concurrently.

Pity about the USER_HZ = 100 thing to accomodate all the borken programs that pick up HZ from the linux kernel header file and assume it is a) constant, or worse yet b) 100.
Had HZ had been a proper syscall instead of a #define in the first place for user-land programs this would not have been a problem today.

Can someone do me a big favor and post RedHat 8.0's asm-i386/param.h file so I can see how they defined HZ, USER_HZ and friends? I'd like to see it without actually going to the trouble of installing RedHat 8.0.

http://www.uwsg.iu.edu/hypermail/linux/kernel/0210 .1/1767.html

In case this get slashdotted, here is RMS' post (and I quote):

The new restrictions on Bitkeeper, saying that people who contribute
to CVS or Subversion and even companies that distribute them cannot
even run Bitkeeper, have sparked outrage. While these specific
restrictions are new, their spirit fits perfectly with the previous
Bitkeeper license.

The spirit of the Bitkeeper license is the spirit of the whip hand.
It is the spirit that says, "You have no right to use Bitkeeper, only
temporary privileges that we can revoke. Be grateful that we allow
you to use Bitkeeper. Be grateful, and don't do anything we dislike,
or we may revoke those privileges." It is the spirit of proprietary
software. Every non-free license is designed to control the users
more or less. Outrage at this spirit is the reason for the free
software movement. (By contrast, the open source movement prefers to
play down this same outrage.)

If the latest outrage brings the spirit of the non-free Bitkeeper
license into clear view, perhaps that will be enough to convince the
developers of Linux to stop using Bitkeeper for Linux development.

I think the website was having troubles. Try again. I just did and it worked fine.

But even better, here is the kernel archives URL for RMS' comments and the response.

Kirk

It is a really efficient way to do this. It was initially done, I think, in 1984 or 1985...

I think the code that's there is for BSD 4.3, but if you've already done the library work...

The overview reads:

This is the Purdue/ksb entombing system. Files removed by programs
linked with "libtomb" are cached for a while (long enough to get on a
backup tape would be best case) in case their untimely loss is noticed.

The 3 programs are "unrm" (the user agent to get files back), "entomb"
the system agent to cache a file, and "preend" (the system agent to
clean the older files from the tombs.

Included as nifty side products are "rmfile" which helps novice users
delete files with funny names (like "-") and "untmp" which should be
used to clean /tmp from a ".logout" type file from casual users.

Since I learned Unix on the big shared machine, I always thought it was built into the OS from the beginning. Was almost dissapointed when I installed Linux and found out it was something they added.

I don't remember all the particulars, but they had a "Charon" daemon that handled the deleted files. You had a pretty good chance up to a couple of days of recovering files, then they were permanently gone.

Someone is working on this for FreeBSD, but I haven't seen a Linux equivalent.

Instigator of "GNU/Linux" Issues Public Apology comments on [OT] Why Stallman says GNU/Linux .

For those of you who don't subscribe to the Linux kernel development mailing list, it was absolutely not a case of XFS just being accepted, there was a HUGE flamewar about it, which only ended a few days ago.

Mailing list archive

Just search in the page for XFS and you'll find the thread.

He instisted in keeping in synch with both the stable and unstable versions and the killer was here followed by Linus making the changes and ESR never updating to match.

Sigh, you see, this is why I don't usually bother reading below "1" - too many brainless ACs.

Now, looking at the pictures (which I assume you haven't), what do we have here then? Hmm? Why it's a palette trolley. Moving right along we can see the three strong men pulling a... why it's a palette trolley. Well I'll be gosh darned.

Next time, try looking before arguing, idiot. /me changes threshhold back to +1...

Sigh, you see, this is why I don't usually bother reading below "1" - too many brainless ACs.

Now, looking at the pictures (which I assume you haven't), what do we have here then? Hmm? Why it's a palette trolley. Moving right along we can see the three strong men pulling a... why it's a palette trolley. Well I'll be gosh darned.

Next time, try looking before arguing, idiot. /me changes threshhold back to +1...

2) From a message on LKML:

PS: flames about why we are supporting the XBox (a design of the Evil Empire) will be summarily ignored. I can only point you to it's HDTV, NTSC, PAL, and possibly VGA outputs, it's dvd/cd drive, and it's $199 USD price tag.

Not to mention M$ takes a loss for every hardware unit sold.

2) From a message on LKML:

PS: flames about why we are supporting the XBox (a design of the Evil Empire) will be summarily ignored. I can only point you to it's HDTV, NTSC, PAL, and possibly VGA outputs, it's dvd/cd drive, and it's $199 USD price tag.

Not to mention M$ takes a loss for every hardware unit sold.

Whoops.

and i think this picture is more interesting !

it works like this , a link gets posted on slashdot. every filthy animal here - including me , you look at pictures instead of reading the article. Suck up all the bandwidth of the server and all your bandwidth are belong to us. its a lame way of doing DOS

Although the pics are very high-rs, apparently Internet2 is very blurry.

"is there an echo in here?"

• POOMA - a high-performance mathematics C++ framework
• Blitz++ - a C++ mathematics library which uses template metaprogramming to achieve FORTRAN-caliber performance.
• MTL - another example of template metaprogramming.
• oonumerics.org - a good site for information on high-performance object-oriented code.

Linus said that is a relly bad idea if you compile things by yourself, but I admit I don't know if that is still a valid argument.

First, thank you Gogo for the link, I have been wanting to know what was in SP3 all week. Second, to be fair microsoft has writers and secretaries and corporate accounts to cater too. Alas the SP3 update is a major update, NT service packs are almost as important as new OS's to enterprise customers. Whereas second decimal point Kernel releases are frequent. Changelogs are written by Kernel developers that can better spend time kernel hacking than making organized concise changelogs. All things considered Marcelo has done a good job compiling this log, if you want more information on any change just do a search for it or the developer who contributed it in the Kernel mailing list.

"hmm, sacrilicous" HS

If you use Linux or Windows, you have a TiVo for the radio now. See Linux Radio Timeshift HOWTO.

If you use Windows, try: Nowhere Man - Messer's Home Page.

There is probably something for the Mac, but I wouldn't know.

Both solutions require that you have an external radio tuned to the station that you want or a Radio Card you can control from your OS. Unfortunately neither Windows or Linux is capable of waking up from a deep sleep via the computer's clock (this is ridiculous, somebody should fix this and offer a smarter computer/BIOS), so it isn't exactly the same as a VCR for the radio. But if you leave your computer on all the time anyway, it doesn't matter.

Dara Parsavand

I believe Alan Cox, for one, is opposed to it in its current form. See here and here.

...wouldnt know QA if it hit them on the head with a mallet...

The argument thread is here. To me it looks like Keith wants it done right now, isn't willing to wait, and thinks the only reason it's being held up is because Linus is a prick.

Personally, I don't know if Linus is right or not. Maybe it can be merged this way, and maybe it can't. But he is doing something about it, and if he's wrong, that will become evident fairly soon.

Despite staunch opposition from certain developers, Linus has recently started to maintain the kernel using the non-free BitKeeper SCM product, which is not only proprietary but also uses undocumented file formats, making interoperability difficult or impossible. Do you think it's fair to encourage developers who would otherwise keep to Free Software to turn to a proprietary solution and what is in effect, shareware?

The land speed record is not how fast your network is in aggregate. It's how fast and how far you can push a single pair of hosts using TCP. How fast the backbone links are on CANet is entirely irrelevant. Lot's of big providers have links running at OC-12 or OC-48, both of which are faster than 400Mbps. Abilene itself routinely runs links at over 400Mbps 24/7. Check out the graphs

But how fast an aggregate link is isn't the point. It's how fast you can send data from one computer to another. If you've ever actually tried to send data at over 100Mbps on the WAN, you would know how hard it is. To get 400Mbps requires the link to not only be fast enough, but to have essentially zero loss. And to get several networks that are that clean, especially to Europe, is pretty amazing. If you don't believe me, try sending a CD's worth of data across your room at that speed. Never mind sending it across the Atlantic Ocean.

Itanium chips could do extremely well on many of the STL algorithms. (I have wondered if the Intel Optimizing compiler for Itanium would do massivly parallel ops with valarray classes. Does anyone have experience there?)

I'm not aware of any compilers, for IA-64 or for any other arthitecture, that do special things with std::valarray. My impression is that the people who care about high-performance matrix computation in C++ are spending more effort on things like MTL and Blitz than on valarray.

It's a pity, in a way. The C++ standard was deliberately changed, in subtle but important ways, to allow implementers to do clever optimizations with valarray. But if any implementers have taken advantage of that freedom, I haven't heard about it (and I'm in touch with enough people so that I probably would have).

Some stats? Just by knowing how much more well-defined C++'s type-system is compared to C is enough to get an intuitive sense that there will be cases where C++ will out-perform it. As for a specific example, type-based alias analysis is one that seems to have been getting attention lately. C++'s templates, are probably the most remarkable example, as they can permit optimizations beyond the ability of current Fortran compilers.

Both of them are so fast already though that comparing them for the most part isn't all that interesting. Awhile back, Alexander Stepanov created the Abstraction Penalty benchmark to test the effect of using abstraction features in C++ like the STL. Over the past several years I've noticed that the penalty is usually close to nothing, if not sometimes less than -- indicating a speedup.

I remember when there was a prank or two on the Net and everyone got a good laugh out of it. But every site cranking out tedious joke after tedious joke -- enough already. Of course, I'm speaking to the audience that thinks recursive acronym project names and cutesy-stupid Gnome release names are funny.

Remember the post from "Linus" to the LKML demanding that the free software community practice better personal hygiene? That's the sort of thing I want to be seeing.

Whatever happened to Shoeboy anyway?