"Both of these articles allude to the fact that I'm working on putting the D-Bus protocol into the kernel, in order to help achieve these larger goals of proper IPC for applications. And I'd like to confirm that yes, this is true, but it's not going to be D-Bus like you know it today. Our goal (and I use 'goal' in a very rough term, I have 8 pages of scribbled notes describing what we want to try to implement here), is to provide a reliable multicast and point-to-point messaging system for the kernel, that will work quickly and securely. On top of this kernel feature, we will try to provide a 'libdbus' interface that allows existing D-Bus users to work without ever knowing the D-Bus daemon was replaced on their system."
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Member since:2009-05-19
Member since:2005-07-08
Really? FUSE and udev were implemented under his watch. Linus is not a very ideological person. He opposed microkernel architecture for pragmatic reasons, mainly because running device drivers in userspace leads to poor interrupt response times.
But as we've seen with hybrid kernels like NT and XNU, there is still value to microkernel architecture even if the device drivers and resource abstractions are mapped onto every address space for performance reasons.
If Linux had embraced a more microkernel-like architecture with a kernel message bus, we might have avoided the whole saga of excising the Big Kernel Lock and the BH device drivers which severely hampered the kernel's ability to scale on SMP hardware.
There is still a stigma in the Linux community about microkernel design aesthetics, probably best demonstrated by the meager adoption of the workqueue interface introduced in the 2.5 series. This allows drivers to queue their work to run on a pool of kernel threads, where they can use sleeping locks and blocking I/O for easy concurrency. But the inclination is to avoid sleeping or blocking and use tasklets instead, even though tasklets are strictly serialized against themselves and do not scale on SMP hardware.
Here we are in 2013, and we're still so worried about the overhead of switching a stack pointer that almost all of our device drivers are single-threaded, and the few that aren't (network and scsi) resort to per-cpu data structures and other tricks because they are running in interrupt context and cannot block.
Member since:2011-01-28
butters,
"If Linux had embraced a more microkernel-like architecture with a kernel message bus, we might have avoided the whole saga of excising the Big Kernel Lock and the BH device drivers which severely hampered the kernel's ability to scale on SMP hardware."
I really enjoy dissecting technologies, especially how it could be made better, but if we don't tread carefully, it often devolve into a religious spat 
"Here we are in 2013, and we're still so worried about the overhead of switching a stack pointer that almost all of our device drivers are single-threaded, and the few that aren't (network and scsi) resort to per-cpu data structures and other tricks because they are running in interrupt context and cannot block."
Do you think it's really a problem? Why would a single threaded driver be a problem when the hardware it controls needs to be programmed sequentially anyways? I'm not really sure what kind of hardware would benefit from concurrent threads trying to program it at the same time without a mutex?
At an event earlier today, Microsoft unveiled the next Xbox - the third model, but confusingly named Xbox One. The big focus was TV, integrated Kinect, and all the other stuff we all expected to be forced down our throats. I think it took them 25 minutes to actually come to what should be the core of the story: gaming. Nothing groundbreaking in the gaming department, except for how Microsoft intends to handle the used games market and borrowing games from friends: pay up, buddy!
The day has finally come! Jolla has finally announced the launch device for its Sailfish operating system - and by god this is a looker. It's decidedly different from other phones out there, but it has good specifications and carries a relatively reasonably price tag - EUR 399, and it's up for pre-order today, shipping in the fourth quarter of this year.
Why does Google get so much credit in the technology industry? Why, despite the company's many obvious failings, do many geeks and enthusiasts still hold a somewhat positive view on the all-knowing technology giant? A specific talk at Google I/O this week provides the answer.
OSNews is a sponsor of this year's O'Reilly OSCON in Portland, Oregon, USA. A lucky OSNews reader will win a free three-day pass, including two tutorials days. To win the pass, post a comment on this story saying something about Open Source Software or OSCON. We'll pick a winner at random next week. If you don't have an OSNews account, you may email us your entry. Part of the conference is the 9th annual Open Source Awards, and today the 16th is the deadline for nominations. If you'd like to nominate an outstanding open source contributor, do it here. Read on for more information about OSCON. Update: The 20% discount code for OSNews readers is "OSN."
"Windows is indeed slower than other operating systems in many scenarios, and the gap is worsening." That's one way to start an insider explanation of why Windows' performance isn't up to snuff. Written by someone who actually contributes code to the Windows NT kernel, the comment on Hacker News, later deleted but reposted with permission on Marc Bevand's blog, paints a very dreary picture of the state of Windows development. The root issue? Think of how Linux is developed, and you'll know the answer.
This is one of those news items that's fun to write, fun to read, fun to comment on, and where no one will be able to say anything unkind. It's all just one big ball of awesome fluffiness. TuneTracker, the BeOS radio automation software, has just released something very special: TuneTracker System 5, the first version designed entirely and specifically for Haiku. In fact, it actually includes Haiku in the software package. Better yet, TuneTracker also unveiled several system-in-a-box products - which have Haiku and TuneTracker pre-installed.
Exactly twenty years ago, a document was published that played a huge role in establishing the web as we know it today. Twenty years later, and this simple and straightforward document is proof of an irrefutable fact: while closed technologies can change markets, open technologies can change the world.Oh multitasking. That staple of computing that got thrown out the window with many modern smartphones. We got some rudimentary thing in its place - but even as multitasking on phone and tablets improves, its user-visible side remains cumbersome. Windows 8 has a neat implementation, and now it's time Android follows in it footsteps.They're here! Whether that excites you or not remains to be seen, but the Galaxy S4, which will most likely become the best selling Android smartphone of the year by a huge margin, has been reviewed by all the major sites, and there's lots of interesting conclusions in there - although I think most of you will get the gist.Nokia has posted its quarterly results for the first quarter of 2013, and just like the quarters that came before, there's not a whole lot of good news in there. The rise in Lumia sales still can't even dream of making up for the sales drop in Symbian phones, and when broken down in versions, the sales figures for Windows Phone 8 Lumias in particular are very disappointing. In North America, Nokia is getting slaughtered.
Member since:
2005-07-08
Not as long as Linus has anything to say about Linux development as he opposes to micro-kernel architectures.