Linked by Thom Holwerda on Wed 9th Nov 2011 21:26 UTC, submitted by edwin
Way back in 2002, MIT decided it needed to start teaching a course in operating system engineering. As part of this course, students would write an exokernel on x86, using Sixth Edition Unix (V6) and John Lions' commentary as course material. This, however, posed problems.
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RE[7]: binary for windows....
by bogomipz on Sat 12th Nov 2011 16:35
in reply to "RE[6]: binary for windows.... "
Member since:2005-07-11
Not really a kernel problem as the dynamic linker isn't really in the kernel.
Sorry, I should have said that the process of loading the binary is kept simple.
When something is statically linked, the library is dissolved, what is not used the dead stripper should remove.
Yes, this is why dynamic linking does not necessarily result in lower memory usage.
Your system is not like static linking. It's like baking dynamic linking.
This is where I do not know what you are talking about.
Creating a static library results in a library archive. When linking a program, the necessary parts are copied from the archive into the final binary. My idea was simple to postpone this last compilation step until install time, so that the version of the static library that the package manager has made available on the system is the one being used.
This way, the modularity advantage of dynamic linking could have been implemented without introducing the load time complexity we have today.
RE[8]: binary for windows....
by moondevil on Sat 12th Nov 2011 17:00
in reply to "RE[7]: binary for windows.... "
Member since:2005-07-08
RE[8]: binary for windows....
by jabjoe on Sat 12th Nov 2011 19:00
in reply to "RE[7]: binary for windows.... "
Member since:2009-05-06
Sorry, I should have said that the process of loading the binary is kept simple.
At the cost of making updating or subsisting more complicated and run time subsisting impossible or more complicated.
Yes, this is why dynamic linking does not necessarily result in lower memory usage.
Only if you have one thing using the lib, or everything is barely using the lib and the dead strip gets most of it. It would be a very very rare case when it uses less disk or less RAM.
Creating a static library results in a library archive. When linking a program, the necessary parts are copied from the archive into the final binary.
Linking isn't just libs, it all the object files. A static lib is just a collection of object data. Linking is putting all this into a executable. With static linking it doesn't have to care about keeping stuff separate, you can optimize how ever you like. Your system would mean that you would need to keep the lib distinct. Think about when a function is called, you can't just address the function, why, because the lib sizes will change, thus the file layout, thus the address layout. So you call to a jmp which you change when you bake the libs. You do that, or you have to store every reference to every function in every lib and update them all at time of baking. Which isn't what you would do as it's insane. You would do the jmp redirection and keep the lib distinct. Your system is more like dynamic linking than static linking.
Right I've done a quick test using lsof and python, totalling up the file sizes for shared object files for all and unique. This gives a rough idea how much memory the current system uses and how much your would use.
Current system: 199 meg
Your system: 1261 meg
Disk will be worse because it will be everything, not just what is running. Might still not be much by disk standards, but by SD standards....
So although I still don't think the biggest thing is space used (it's management and simplicity), it certainly shouldn't be discounted.
Very smart people have been working on this kind of thing for many decades and there is a reason things are like they are.
News
Linked by Thom Holwerda on 05/18/13 21:06 UTC
"At the end of a week in which Electronic Arts confirmed it wasn't developing a thing for the Wii U, one of the software engineers in EA Sports' Canada studio, in a series of since-deleted tweets, disparaged the console as 'crap' and suggested Nintendo should give up on hardware altogether. 'The Wii U is crap. Less powerful than an Xbox 360. Poor online/store. Weird tablet', tweeted Bob Summerwill, listed as a senior software engineer at EA Canada, in a reply to a tweet posting a link about EA's no-Wii U news. 'Nintendo are walking dead at this point'." The Wii U is turning into the 21st century's Virtual Boy.
Linked by Thom Holwerda on 05/18/13 7:37 UTC
"In NixOS, the entire operating system - the kernel, applications, system packages, configuration files, and so on - is built by the Nix package manager from a description in a purely functional build language. The fact that it's purely functional essentially means that building a new configuration cannot overwrite previous configurations. Most of the other features follow from this." Interesting approach. A Linux distribution, sure, but with some very refreshing ideas about system configuration.
Linked by fran on 05/18/13 1:38 UTC
Appfour added, among other features, C/C++ support to its new version of AIDE. From Android-IDE, "Now you can write parts of your app or your whole app in C/C++ on your device. AIDE supports the Standard Android NDK toolchain (GCC 4.6 + Bionic, STL, ...). No changes are necessary if you want to build an app developed on a PC with Eclipse. C/C++ development is fully integrated: Build errors appear in the error list and files can easily be navigated to with Go to file. The editor supports C/C++ syntax highlighting."
Linked by Thom Holwerda on 05/17/13 23:35 UTC, submitted by kragil
Ars nails it: "The answer is that Google did announce what amounts to a fairly substantial Android update yesterday. They simply did it without adding to the update fragmentation problems that continue to plague the platform. By focusing on these changes and not the apparently-waiting-in-the-wings update to the core software, Google is showing us one of the ways in which it's trying to fix the update problem."
Linked by MOS6510 on 05/17/13 22:22 UTC
"It is good for programmers to understand what goes on inside a processor. The CPU is at the heart of our career. What goes on inside the CPU? How long does it take for one instruction to run? What does it mean when a new CPU has a 12-stage pipeline, or 18-stage pipeline, or even a 'deep' 31-stage pipeline? Programs generally treat the CPU as a black box. Instructions go into the box in order, instructions come out of the box in order, and some processing magic happens inside. As a programmer, it is useful to learn what happens inside the box. This is especially true if you will be working on tasks like program optimization. If you don't know what is going on inside the CPU, how can you optimize for it? This article is about what goes on inside the x86 processor's deep pipeline."
Linked by Thom Holwerda on 05/17/13 22:15 UTC, submitted by Tom
"It was the only moment I heard regret slip into Otellini's voice during the several hours of conversations I had with him. 'The lesson I took away from that was, while we like to speak with data around here, so many times in my career I've ended up making decisions with my gut, and I should have followed my gut,' he said. 'My gut told me to say yes.'" The world would've been a much different place - Apple would have been less dependant on Samsung for its chips, which probably would've meant less money for Samsung to develop its Galaxy business.
Linked by Thom Holwerda on 05/16/13 21:41 UTC
Glass is getting some love at Google I/O as well. New applications have been released - Facebook, Twitter, Evernote, Elle, Tumblr, and CNN. Perhaps more interesting: the newly announced Google Glass Developer Kit will allow offline applications and direct hardware access - great for hacking and expanding Glass' potential. This kit will really allow hackers to put Glass through its paces.
Linked by Thom Holwerda on 05/16/13 17:04 UTC
"But Beck and Merrill decided that simply banning toxic players wasn't an acceptable solution for their game. Riot Games began experimenting with more constructive modes of player management through a formal player behavior initiative that actually conducts controlled experiments on its player base to see what helps reduce bad behavior. The results of that initiative have been shared at a lecture at the Massachusetts Institute of Technology and on panels at the Penny Arcade Expo East and the Game Developers Conference." Absolutely fascinating stuff. I'm a League of Legends player, and to be honest, the community isn't nearly as bad as some make it out to be. I'm happy Riot games has the guts to employ science to address the issue.
Linked by Thom Holwerda on 05/16/13 13:17 UTC
"Android and iOS, the number one and number two ranked smartphone operating systems worldwide, combined for 92.3% of all smartphone shipments during the first quarter of 2013 as Windows Phone crept past BlackBerry for 3rd place. According to the International Data Corporation Worldwide Quarterly Mobile Phone Tracker, Android smartphone vendors and Apple shipped a total of 199.5 million units worldwide during 1Q13, up 59.1% from the 125.4 million units shipped during 1Q12." Windows Phone doubles from a few to twice few, iOS loser market share as its growth is slower than that of the overall market. BlackBerry continues slide into irrelevance.
Linked by Thom Holwerda on 05/16/13 12:06 UTC
"According to the latest research from our Wireless Smartphone Strategies service, global Android smartphone profits reached US$5 billion in total during the first quarter of 2013. Samsung dominated and captured an impressive 95 percent share of all Android smartphone profits." Wow.More News »
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Not really a kernel problem as the dynamic linker isn't really in the kernel.
http://en.wikipedia.org/wiki/Dynamic_linker#ELF-based_Unix-like_sys...
When something is statically linked, the library is dissolved, what is not used the dead stripper should remove. Your system is not like static linking. It's like baking dynamic linking.
Then you kind of loose some of the gains. You have to have dependencies sitting around waiting in case they are needed. Or you have a repository to pull them down from....
That was my point.
Yes.
As I said before, it's not really static, it's baked dynamic. Also if you have dependencies separate you either have loads kicking about in case they are need (Windows) or you have package management. If you have package management all you get out of this is baking dynamic linking. For no gain I can see.....
It's quite different as it's decentralized using these application folders. Application folders are often put forwards by some as a solution to dependencies.