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Embedded Linux 1-Second Cold Boot To QT
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."
I assume they mean Qt application, not QuickTime, or whatever.
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.
...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.
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.
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.
Any details on what they've done? Is it largely hardware-specific initialisation, or have they made changes that would be useful on a traditional desktop?
From the article:
"We've not applied any specific intellectual property but instead spent time analysing where boot delays are coming from and simply optimising them away. The majority of the modifications we make usually fall into the category of 'removing things that aren't required', 'optimising things that are required', or 'taking a new approach to solving problems' and are tailored very precisely to the needs of the 'product'."
Also:
"If you're interested in exactly what modification I made and a little more about the approach taken - you may be interested in these slides [http://www.slideshare.net/andrewmurraympc/elce-the] which I presented at ELC-E 2010"
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.
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
The bleedin' slideshow requires Flash 9 , for crying in a bucket! Why the hell do you need Flash to show a sequence of static images in succession!? And to download the slides, you have to have two accounts: one on Facebook, and one on something called Slideshare.
Screw it.
</rant>
(Be glad I'm sparing you my take on Javascript.)
I refuse to believe corporations are people until Texas executes one. -- desert rain on http://www.dailykos.com/user/
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.
I'd be willing to bet they are doing software boot process monitoring and know exactly how long it takes to boot.
Liberty.
Um. This capability has been around since FOREVER. I worked at MS 'beside' the group that created exactly such a tool, called BBT. This was ~2000.
It was the most used, but not the only result of a tool suite called Vulcan. This would allow you to pull apart and re-assemble a binary, either for re-ordering (optimization) or to add instrumentation for other optimization projects (like the one I worked on).
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
You forgot to mention the performance died when marketing made you link in ie.h .
Got Code?
Um. This capability has been around since FOREVER. I worked at MS 'beside' the group that created exactly such a tool, called BBT. This was ~2000.
It was the most used, but not the only result of a tool suite called Vulcan. This would allow you to pull apart and re-assemble a binary, either for re-ordering (optimization) or to add instrumentation for other optimization projects (like the one I worked on).
You deliberately seem to miss one really important point.
These guys do not have to pull apart binaries they can mod them from source if they feel like it. You have let the cat out of the bag and admitted that Microsoft uses disassemble technique on other peoples binaries all the time. No wonder it was so easy for you guys to clone closed functions in IBM's Lotus Suite and com SQL framework, then pretend that you did not know what was going on when all of a sudden their binaries were slower and less reliable than yours!
So you guys have been doing what you say others have no business do to your software FOREVER. Face it... considering the fact that embedded Linux runs most TVs, BD players and other really popular devices on the market today, you are just mouthing a party line and not making a real valid argument why MS is losing out in the embedded products market!
...and what the hell is wrong with using a pre-configured suspend image anyhow? seems like a lot of effort wasted IMO.
I hate slideshare. What ever happened with good old Pdf downloads? But now Pdfs need to be embedded in Web2.0 crap. We ain't on the cloud yet, every PC out there have have a Pdf viewer installed. If they at least would use JavaScript so you don't need Flash for it like Google Maps.
"Download is disabled by the owner". If the owner don't like the Pdf be in public than why the hell are they posting it on a freely accessible website? Does the owner really thinks I'm going to copy it and distribute it as my own work? Does the owner trusts me with nothing? Should I blank my brain after I saw the slides?
If the owner want that I see his stupid slides then he should trust me more and not forbidding me of open my favorite Pdf viewer, print the slides out or to copy his stupid slides on a different device.
He can take his slides and put them where the sun don't shine. Then he can be really sure that nobody is going to copy his work.
http://www.mueller-public.de - My site http://www.anr-institute.com/ - Advanced Natural Research Institute
My thoughts exactly, I don't want to use non-free adobe flash and slideshare does not work with gnash. Fortunately a very similar looking PDF does seem to be available at
http://elinux.org/images/f/f7/RightApproachMinimalBootTimes.pdf