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User: diegocgteleline.es

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  1. Re:I preferred the old odd/even split on Time for a Linux Bug-Fixing Cycle · · Score: 3, Insightful

    With FreeBSD 5.x, if you had a working system

    I'm not saying you couldn't choose a stable FreeBSD version - you can run a 2.4 kernel if you don't like 2.6, aswell.

    I was talking about development models. 5.X was a disaster, and this is something that even the core FreeBSD developers have accepted (they have changed a bit their development model to avoid the 5.x disaster again, you know): Too many time, too unstable, too many time to stabilize. 6.1 (which was released today, BTW) is great, sure. That doesn't means the development model is the best

  2. Re:Typical monolithic kernel problem on Time for a Linux Bug-Fixing Cycle · · Score: 3, Insightful

    Any kernel with upwards of 2.5 million lines of code is going to be incredibly buggy

    You mean that a microkernel is magically going to implement the same funcionality than linux, with all the thousand of driver, with its support for docens of hardware platforms, in less of 2.5 millions of lines of code?

    Sure, a "microkernel" itself doesn't takes a lot of code. But BECAUSE it's a microkernel, drivers, filesystems, networks tacks etc. need to be implemented as servers. Implementing servers that implement the same funcionality than linux has today would take more of 2.5 milliones of lines, for sure. And those servers can have bugs, you know. And hardware bugs exist - it's completely possible (too easy, in fact) to hang your machine by touching the wrong registers no matter if you're using a microkernel or not.

    Also, I don't understand why a microkernel would be magically more maintainable than a monolithic kernel. As far as I know, software design is something that doesn't depends in whether you pass messages or not. Sure, a server running in userspace can't take the system down. But that's completely unrelated to modularity and mainteinability. Microkernels were in fact invented because people though that hardware complexity wouldn't allow to continue running monolithic kernels, ignoring the fact that it's perfectly possible to write a mainteinable monolithic kernel with modular design - which is how Linux, Solaris internals etc. are today - just like it's completely possible to write a unmainteinable, non-modular microkernel. It all boils down to software design. And guess what: Current general-purpose monolithic kernels (linux, *BSD, Solaris, NT, Mac OS X - no, a operative system that implement drivers, filesystems and network stacks in kernel space it's not a microkernel) have had a lot of time and resources ($$$) to become mainteinable and modular, extensible, etc.

    It's fun how when a monolithic kernel has a bug it means microkernels are better, like a microkernel model magically makes coders bug-free, or like it's not possible to write a microkernel server with a bad API that forces all driver developers to patch their drivers to fix a security bug. I'd love to hear what development model would use the Hurd/QNX/whatever guys to maintain six millions of lines of code, be it driver for a monolithic kernel or drivers implemented as microkernel servers.

  3. Re:Standardize the Kernel API!! on Time for a Linux Bug-Fixing Cycle · · Score: 1

    The problem is that the drivers have to remain in constant flux because the kernel API is always changing

    Well, this is just a consequence of what people is discussing. In the current 2.6 model you're allowed to merge new features (ie: things that break the kernel API). What you're proposing is to go back to the stable/unstable development model.

    But I don't think the "changing kernel API" is the source of problems - if a driver doesn't work, it's because it doesn't have a good maintainer. Releases take around 2 months currently in the linux kernel, if a driver maintainer can't take care of a driver in a two months timeframe then the driver doesn't have a good maintainer. Is not that because the kernel api is not stable, driver maintainers need to rewrite drivers in every release, either; and when a "invasive" change is done to introduce a new feature, its not rare that the guy who breaks things and introduces the new feature is forced to port the drivers to the "new api" to get his changes in. But you can find tons of drivers that have not been touched deeply in more than 6 months. And the ones that have been patches recently have probably been patched because the maintainer was working in something related to the driver, not "trying to fix kernel API breakage"

  4. Re:I preferred the old odd/even split on Time for a Linux Bug-Fixing Cycle · · Score: 5, Insightful

    The "stable/unstable" development model does not work so well with huge projects like the linux kernel is.

    With the old model, the linux kernel would start a unstable release and people would start adding stuff which not the care you'd put into merging something in a stable tree, is not tested a lot, etc...

    Now keep this for one, two years. When you decide to release the unstable tree as the next stable version you realize that your unstable tree is full of crap, and you need to waste months or years (Vista) trying to stabilize it. Even when you release the .0 version it's still unstable, so people has to wait even more months to start using it.

    The "new" development fixed that. In the current linux development model people is allowed to put new features in the kernel even if they're invasive. But programmers are not allowed to put crap in the kernel, they need to be VERY WELL tested (in the -mm tree) and reviewed, show numbers that back your words if neccesary, document things, etc. Of course no code is free of bugs, so the released version will not be 100% stable as current 2.4 is, but it's QUITE stable.

    Because the features are merged progressively, it's MUCH easier to find and fix bugs. Even if there're new features in every release, there're not a LOT of new features - it's much easier to find out what feature broke something between two releases. Compare it with a stable/unstable development model: People keeps adding things for years, when the user switches from 2.4.x to 2.6.0 his kernel doesn't boot. How do you find out who broke that with so many changes?

    IMO, from a Q/A POV, the new development model has more sense than a pure stable/unstable development model. It's about "progressive" vs "disruptive", and for projects with several millions of lines and so many contributors it may have sense. Of course, because new things got added there're always some bugs, which is what people is bitching about today. Maybe this could be fixed by leaving the current tree as "stable" and start a new tree - but instead of a "unstable" 2.7 tree, a 2.8 "stable" tree. A pure unstable release doesn't works that well with huge projects like the linux kernel. Remember the hell that FreeBSD 5.x was and how much has affected to the FreeBSD project, remember windows Vista. Maybe it works for some people, but I don't thing it's the best development model for such projects. Solaris is also using this model to some extent - they release things into opensolaris, but what you see in opensolaris is not the "official stable release", it only becomes "stable" after a while.

  5. Re:Feh. on Microkernel: The Comeback? · · Score: 1

    What are microkernels supposed to do? Move things to userspace

    What does NT do? implement everything in kernel space, including stuff that does not really need to be there, like the graphics subsystem and the window manager.

    I fail to see where the "microkernel concepts" have been left. NT and Mac OS X are great examples of how to turn a pure microkernel into a monolithic kernel.

  6. Re:Feh. on Microkernel: The Comeback? · · Score: 2, Informative

    NT is not a microkernel. Microkernels are supposed to mve things like drivers, filesystems, network stacks, etc, to userspace.

    Where does NT implements all that? In kernel space. A NULL pointer in that code brings the system down.

    Just because it was STARTED from a microkernel (like mac os x) doesn't means it's a REAL microkernel. How can you call "microkernel" to something that implements the filesystem in kernelspace?

  7. Re:multicompartment isolation on Microkernel: The Comeback? · · Score: 1

    critical driver goes *poof!* the system still goes down.

    Not to mention that hardware bugs exist. A driver, be it in userspace or kernel space can block your computer by touching the wrong registers.

  8. Re:How hard... on Microkernel: The Comeback? · · Score: 1

    IMO, it'd be much easier to progressively move things to user space than writing a microkernel from scratch. Saying "let's write a microkernel from scratch" is just like saying "we're goint to write a complete desktop from scratch, with a complete office suite and everything!". Not feasible in practice - too many efforts. It's completely possible to write a "microkernel API" in the linux kernel if some day it has sense. People has been also experimenting with userspace drivers

  9. Re:Feh. on Microkernel: The Comeback? · · Score: 1

    Tanenbaum's research is correct

    Tanembaum's research is wrong in some ways - specifically when it comes to analyzing monolithic's kernel problems.

    I see people hitting YEARS of uptime with Linux/BSD/Solaris and hell, even win2k machines. Sure, microkernels will come back the day monolithic kernels can't be stable and secure. As for today, I'd say that monolithic kernels are IMPROVING when it comes about reliability and security. Compare Windows 9x and XP, for instance, and Vista is getting even better.

    easier to maintain

    I don't see how. You know, microkernels don't have better code design than monolithic kernels, neither the other way around. Software design is something that does not depends in using message passing or not. It's perfectly possible to write crappy microkernels and it's possible to write modular and mainteinable monolithic kernels (which is what Torvalds has been saying for years)

    Guess why people uses Linux and Solaris? Unlike it happens in microkernels, people has wasted many millons of dollars and hours making it mainteinable and modular - take a look at Linux's block layer, where you can switch to different I/O schedulers at runtime (echo foobar > /sys/block/hda/queue/scheduler); and then you can insmod and rmmod ioschedulers at runtime aswell. Now. that's what I call modularity

    One of the reasons microkernels were born is because people though that monolithic kernels wouldn't be able to cope with future hardware because it'd be too complex, they though that you couldn't write modular and mainteinable monolithic kernels. See, the hardware complexity increased, and monolithic kernels are still there. Which is one of the reason why microkernels didn't suceed, IMO - they ignored the fact that you can make monolithic kernels modular and mainteinable. The fact that still today we use them proves they were wrong.

  10. Re:Rewrite it as a microkernel!! on 2.6 Linux Kernel in Need of an Overhaul? · · Score: 1

    Having the daemons running in userspace means that it's much more difficult for them to take down the entire machine if they do have bugs

    They still have buts that need to be fix - and BTW, a driver can hit hardware bugs that can halt the machine no matter what kernel you're using.

  11. Re:Fantastic and Overdue on 2.6 Linux Kernel in Need of an Overhaul? · · Score: 1

    The 2.6 Kernel has been plagued by bad bugs.

    I wouldn't agree with you. 2.6 has been rock solid for me - to me it looks like andrew morton is trying to get things fixed before it gets worse. 2.4 was a nightmare (do you remember people ranting about data corruption, several kernel releases being released in fact with data corruption bugs like 2.4.15, VM changes in middle of a stable series) and it was supposed to be better.

  12. Re:Rewrite it as a microkernel!! on 2.6 Linux Kernel in Need of an Overhaul? · · Score: 3, Insightful

    given that some microkernels are only about 3500-6000 lines of code (as opposed to Linux's million or so)

    Oh yes, but the microkernel doesn't implements almost any user-visible functionality - TCP/IP stack, VFS, filesystems, USB, random devices....

    You know, the linux core kernel is also quite stable. They're the drivers who hit more bugs. A microkernel itself can be perfect, but the userspace daemons implementing funcionality will also have bugs, and those daemons will take more or less the million of lines that linux takes. IOW: microkernels doesn't fix magically bugs.

  13. Re:Not so sure... on El Reg Says Google Choking on Spam Sites · · Score: 1

    Gmail saying that you have whatever number of MB doesn't matters at all. Most of gmail accounts don't use it beyond a few (less than 10) MB, if not KB. What matter is how many size uses people *globally*. I doubt that google has 3 GB * (number of gmail accounts) of size available, and if it has them they probably need them for web search. Your account only uses the neccesary storage when you *use*. Why would gmail need to do the contrary?

  14. Re:This matters to me why? on Electric Car Faster Than A Ferrari or Porsche · · Score: 1

    Maybe I'm just crazy... but I'm sick and tired of hearing about new and grand vehicles that could potentially reduce our dependency on foreign oil, or make the environment clean

    Excuse me, but how on earth is going a electric car going to make the environment more clean? Sure, it works with electricity. But that electricity has to be generated, anyway - in nuclear/coil power plants, etc.

    So I don't see how electric cars solve the problem. Their engines are probably more efficient (less mechanics), but they'll have to move the big amount of weight that is neccesary to make a vehicle stable & safe at standard speeds.

  15. Re:As we all know on Microsoft Trumps Google, Yahoo! R&D Budgets · · Score: 1

    More innnovation is a direct result of spending more money on it.

    I agree with your irony.

    "Innovation has nothing to do with how many R&D dollars you have. When Apple came up with the Mac, IBM was spending at least 100 times more on R&D. It's not about money. It's about the people you have, how you're led, and how much you get it." - Steve Jobs

  16. Return to the 90's on Microsoft Unveils Online Advertising Service · · Score: 2, Interesting

    Ads seem to work for TV but duh, weren't ads who were financiating all those .com bubbles before they bankrupted?

  17. Re:Is mplayer relevant? on MPlayer Developers Interviewed · · Score: 1, Informative

    "monolithic" is what makes mplayer feel to me. It's just me? Lots of options, yes, really versatile, but....

    Don't get me wrong. I've zero idea about mplayer internals, but I wonder why ej: mplayer is a big binary monolith instead of something more modular which can be used by other people.

    Xine may not be perfect, but I've seen people reusing xine in other places: enlightenment 17, for one. Or totem-xine which has, BTW, a firefox plugin to allow people see videos with a gui to handle videos, something that linux desktop has been missing for years (and don't even mention the useful but ugly hack that mozplugger is, please). Not to mention that it's used by nautilus to do things like ej: generate thumbnails. Mplayer may be a good video player, but xine is a *useful* video player.

  18. Re:University rejected on Summer of Code Now Taking Student Applications · · Score: 1

    Google does this for free. I mean, they're giving their money (LOTS of money) for free. Is not that they need to give people excuses, they may very well cancel the SoC program if they'd want.

    IOW: Be polite. They're being already kind enought by doing this, if you aren't accepted sorry - deal with it, is not that google owes you nothing.

  19. Re:Livelihood on Google Staff MD on Carpal Tunnel & RSI · · Score: 1

    I also recommend buying a mouse like this - it helps to keep your arm in a "natural" position. Unless you're a gamer, you won't matter having one.

    I also recommend buying a wrist brace, even if you don't have RSI. It helps to keep your wrist straight - not keeping it straight is what can inflamate the nerve, AFAIK.

  20. Re:the new IE7 Beta 2 on IE The Great Microsoft Blunder? · · Score: 3, Interesting

    What's with eliminating the standard menus that every other Windows program uses?

    You can enable them!. Look here!. The menu is placed between the address bar and the tab bar. The tab and the address bar are both related with the page you're viewing, the menu is not. It's probably the worst place to put such menu: you want to keep such elements in the same place. But hey, this is microsoft - some reviewer will argue that it has sense.

    The UI of IE7 was designed very carefully. They just don't know to do it right. Look at the the latest paul thurrot's vista review:

    http://www.winsupersite.com/images/reviews/vista_5 342_rev5_02.jpg
    http://www.winsupersite.com/images/reviews/vista_5 342_rev5_08.jpg
    (Try to guess which is the active window)

    http://www.winsupersite.com/images/reviews/vista_5 342_rev5_01.jpg
    ("File operations"! great!)

    I've enought problems to make people understand XP (why the extension->program associations are placed under "carpet options"???? Why i need to look at the taskwork's properties to delete the list of recently opened files in the start menu??? Why some visual effects are on the "my pc->properties" window, others in the display's properties and some duplicated in both?? Oh, and wait: in IE7 beta 2 you configure cd-auto-startup in IE's advanced properties). I can't wait for vista, it looks like they'd be trying to be better than mac os x but they keep falling in the second-system syndrome. It's so bad when it comes to usability that is laughable - most of the people knows windows just because they're taugh the basic operations in the school.

    Look at how many XP/office training courses are in your city. It's so fucking bad that people can make money with it.

  21. Re:Sun makes great hardware... on Sun's Scott McNealy's Days are Numbered? · · Score: 1

    Like >90% of Slashdot you apparently haven't worked on enterprise level hardware.

    Like many pro-sun enterprise people you don't seem to realize that the low and middle-end sun servers are all based on AMD CPUs. When they started the move, they didn't even had a 64-bit version of solaris for those CPUs - pretty sucky for a company that had been doing 64-bit computing for nearly a decade. Not a good example of high-quality enterprise hardware, if you ask me

  22. Re:It's Paul Thurrott... on How Vista Disappoints · · Score: 1

    "In the previous version of Mac OS X, version 10.3, Apple introduced a feature for power users called Exposé that seeks to help manage the multiple applications and windows one typically opens in the course of using a Mac."

    It's the "power users" dismissal that irritates me. The bit that says "Macs are for elitists, rather than for you and me." In fact, power users use Command+H and Command+Tab. Exposé is for people like my sister who want/like a simple visual representation of all their windows. Thurrott gets it totally wrong, and I can't help but wonder whether the misunderstanding is deliberate.


    Ah yes, Paul is definetively showing a sign of windows extremism here: "Apple introduced a feature for power users called Exposé". I though that non-power users just used the dock which is much simpler, but I guess I was wrong.

  23. Re:Posix and security on How Vista Disappoints · · Score: 1

    SeLinux and Vista security schemes are two examples of mandatory access control security architecture, where is the vaporware?

  24. Re:It's Paul Thurrott... on How Vista Disappoints · · Score: 3, Informative

    "I've been a Mac fan my entire life"

    "Microsoft is working on similar, if further-reaching, technology for Longhorn. Apple's solution, however, is here right now and it appears to work quite well. Score one for Apple."

    "Overall, I've always been a big fan of Safari, and I'd use it rather than Firefox or IE if it were available on Windows. It's an excellent application."

    "Mac OS X 10.4 "Tiger" is, in fact, a minor upgrade to an already well-designed and rock-solid operating system. It will not change the way you use your computer at all, and instead uses the exact same mouse and windows interface we've had since the first Mac debuted in 1984. That isn't a complaint about Tiger, per se: It's a high-quality release. My issue here is with marketing, not with reality."

    "Apple Mac OS X 10.4 "Tiger" is the strongest OS X release yet and a worthy competitor to Windows XP"

    "And unlike Longhorn, it's shipping any day now. What a concept."

    "The graphics subsystem is substantially improved, if a little obviously modeled after that in Mac OS X. Heck, half of the features of Windows Vista seem to have been lifted from Apple's marketing materials"

    "Windows Vista will still include pervasive index-based searching features modeled, apparently, after the Spotlight feature in Mac OS X."

    My Wife is Switching to the Mac

    Yes, it definitively sounds like the typical Windows who can't write non-biased opinions about other products

    One memorable line from his review of 10.4 had it that Windows XP SP2 was a more significant update than was Tiger, yet elsewhere in that review he just casually pointed out how 10.4 was little more than a large collection of bug fixes

    Maybe because it may very well true? Sorry if it doesn't means the same for you, but the addition of applications to get the time, weather and stocks (nice, but "revolutionary"???), spothlight, quartz 2d extreme (an optimization to an already good graphics subsystem) and core image looks to me like a light addition compared with all the internal features microsoft touched/add in SP2 (rewriting part of the IE UI, rewrite part of the IE internals to handle better the security objects, the add-on manager, the much-improved firewall, the much improved wireless support, the reworked RPC internals, updated directx, the non-executable stack protection. You may argue that Mac OS X already does all what those XP updates do but for XP SP2 is a HUGE jump, much bigger than what 10.4 for mac os x 10.3

  25. Re:Posix and security on How Vista Disappoints · · Score: 1