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Embedded Linux 1-Second Cold Boot To QT

Posted by timothy on from the why-does-my-phone-need-2-minutes? dept.

An anonymous reader writes "The blog post shows an embedded device cold booting Linux to a QT application all in just one second. This post also includes a link which describes what modifications were made to achieve this."

14 of 141 comments (clear)

  1. Re:Ain't that qute? by Anonymous Coward · · Score: 5, Insightful

    If the first thing that enters your mind when reading "QT" is QuickTime, you're on the wrong website I'm afraid.

  2. Re:Ain't that qute? by Anonymous Coward · · Score: 5, Funny

    If he came here for abuse, it's definitely the right website!

  3. Re:Ermm.. by buchner.johannes · · Score: 5, Informative

    The have a slideshow here: http://www.slideshare.net/andrewmurraympc/elce-the , it's interesting starting at slide 19. Especially the executable reordering to defer loading of UI event handling code is impressive.

    --
    NB: The message above might reflect my opinion right now, but not necessarily tomorrow or next year.
  4. yes, my 1990 Acorn A3000... by FuckingNickName · · Score: 4, Interesting

    ...booted in about 5 seconds, and that was to a general desktop.

    And my toy homebrew OS boots to a primitive UI in under 2 seconds after BIOS, and much of that is running interpreted bytecode.

    The fact is that a full BIOS + Linux / Windows system is a horrible fucking mess of bloat, but part of it is the price you pay finding and initialising all those millions of third party devices your old/embedded device isn't going to need to worry about.

    Still, as always, I believe any engineer's claim not before I get to test it myself.

    1. Re:yes, my 1990 Acorn A3000... by sitharus · · Score: 4, Insightful

      Your Acorn A3000 held and executed most of the OS from ROM. When you don't have to copy from disk times are much faster.

      --
      --sitharus
  5. Re:Ain't that qute? by countSudoku() · · Score: 5, Informative

    I had the same reaction. The answer lies in the wikipedia, not in the unhelpful intermediate posts:

    http://en.wikipedia.org/wiki/Qt_(framework)

    Qt "is a cross-platform application framework that is widely used for developing application software with graphical user interface (GUI) (in which case Qt is referred to as a widget toolkit when used as such), and also used for developing non-GUI programs such as command-line tools and consoles for servers"

    --
    This is the NSA, we're gonna geet U h@x0r5! Also, what is a h@x0r5?
  6. Made my day by LoRdTAW · · Score: 4, Interesting

    Its good to see a fun tech article like this on /. I haven't seen any in a while (maybe its just me).

    I assume that during boot time, the Qt UI and low level hardware modules are loaded immediately. Then other modules and services can be loaded later on such as networking, video capture drivers and other lower priority services. I also assume the UI is not based on X but a Qt implementation that is directly drawing to the frame buffer.

    Lately I have been on a bit of an embedded systems kick playing around with PLC's and embedded micro controllers. This is a great article.

  7. Function re-ordering inside the image? wow by RollingThunder · · Score: 5, Insightful

    I have to say, the most impressive/innovative tweak, to me, was the re-ordering of required functions in the compiled binary. Doing so allowed them to reduce load time, by making it that only two blocks had to be demand-read off the flash filesystem, instead of four.

    That's some crazy, use-the-drum-spin-as-timing, innovative thinking right there. Serious kudos.

  8. Re:Function re-ordering inside the image? wow by Chrutil · · Score: 5, Informative

    That's actually common practice in profile guided optimization, put commonly used code close together in the image to minimize the number of pages loaded.

  9. At last! by mr_lizard13 · · Score: 5, Funny

    This is the year of Linux on the de- wow, that was quick.

    --
    "We live in a global world" - Harvey Pitt, former Securities and Exchange Commission Chairman
  10. Re:Function re-ordering inside the image? wow by noidentity · · Score: 5, Informative
    Really? I thought this was standard stuff for profile-guided-optimization. It's common knowledge that when a system initializes, it jumps all over the image, which is bad if it's paged. Seems a big "duh" to reorder functions so that all the init code is together.

    Another optimization that was common old Mac compilers was "dead-stripping", where they avoided linking in any functions that were never called. Apparently this isn't commonly done and instead if a single function in a file is called, then ALL are linked in, at least when I looked into it for Linux a while back.

  11. Re:Ain't that qute? by zish · · Score: 4, Funny

    I know I'm going to get modded "off-topic", but this is getting too silly.

    --
    Spork.

    P.S. Spork.
  12. Re:Function re-ordering inside the image? wow by sp332 · · Score: 4, Informative

    The Story of Mel! http://foldoc.org/The+Story+of+Mel (That's not the original, that's the "free verse" version which is better IMHO.) It might even be a true story! http://en.wikipedia.org/wiki/Mel_Kaye

  13. Re:Ain't that qute? by PopeRatzo · · Score: 4, Funny

    I came here for a good argument.

    I came here to meet lonely singles in my area.

    --
    You are welcome on my lawn.