I've noticed two ways to speed up ChromeOS (and forks) that I *think* (let me know if I'm wrong) would be pretty easy to implement.
First, the filesystem. I noticed chromeos-install seems to use ext4 by default, with just a bunch of "mkfs.ext4" commands...
Could we just swap out all the mkfs.ext4's with mkfs.f2fs, and enjoy a free speedup on SSDs (which most chromebooks have)?
Second, and I'm less sure of how to do this, but using more compile-time optimization (like -O3 instead of -O2). Since ChromeOS is based on Gentoo it should be at least possible. Here's an example of a Gentoo overlay with the sort of optimizations I'm talking about. IDK if this would be plug-and-play or not though with ChromeOS.
Also, let me know if you've gotten any other interesting speedups working
well some expert should check this please....
Related
I've been following threads on here for a few months, and now I think I want to try to learn more about how Android actually works. I'm familiar with IDEs and coding in general(not my strong point), so I think I could pick up some things pretty quickly. Where would you guys recommend I look for learning to code/tweak Android code*?
I kind of want to be able to say I'm running my own cooked up version of Android.
*please ignore this redundant word choice, please.
rougegoat,
There is a fork in the road right at your starting point, strangely enough. You could choose to study Android application development, or you could choose to look at ROM "development". They are almost worlds apart in both nomenclature, toolsets, and skills; and because of the breadth of skills that are needed in both domains, I have no doubt that there are people that are simultaneously geniuses in one of those areas of expertise, and a numb-skull in the other: that's how far apart they are.
The former is all about Java, Android API's, the "SDK", and an IDE such as Eclipse, and emulators and the device bridge; the latter has a distinct "Unix jock" nature to it: Android "NDK", (or CodeSourcery) toolchains, gcc, make, command-line and shell scripting, understanding dynamic linking and execution environments, and use of configuration management tools (git and repo).
When "code" comes up in the former, it's Java; in the latter, ANSI C (or any other native-compiler language, but C is most typical). In the latter case, if you are building source trees from public repositories, (say Cyanogen or AOSP) initially you won't spend any time at all with C - you'll be spending 95% of your time struggling with with the build environment(s) and trying to wrap your head around the mysteries of "git" and "repo" - and also deciphering Unix shell scripts (typically written in the "Bourne" or "Bash" shell dialect) when things go wrong or are poorly documented. And yes, they will go wrong; effectively diagnosing what happened when things go wrong requires solid Unix/Linux skills.
Your question as posed suggests that you are more interested in the OS/ROM side of things than App development; if that is the case I would suggest you:
-brush up or learn from scratch basic Unix/Linux skill sets (they map over to Android almost 1-to-1).
-If you are a Windows user, download VirtualBox, and create a VM with Ubuntu (8.0.4 or 10x); use developer.android.com as a reference for dependencies and setup. Make sure the virtual disk is plenty big: at least 30-40 Gb. Don't attempt to set up a native development enviroment in Windows/cygwin. ( Windows is a great place for the Android SDK and Android App development, but decidedly not for native code development for Android "ROMs"** ).
-Install both the CodeSourcery and the Android "NDK" (Native Development Kit) in your Linux VM, and try and build a smallish, but multi-file C source-code project that uses Makefiles using both of those toolchains. (Sounds easy, right? Wait till you try anything involving the standard I/O library with the NDK).
-Get your simple project code to run correctly on a real phone device.
- Then, download and build an HTC kernel from their (standalone) source tree - try and do it with both toolchains (CodeSourcery and Android NDK) - simply for the experience of setting up the environments correctly.
- Then, learn the basics of dealing with repo, download an Android source tree and compile it - using both toolchains (CodeSourcery and Android NDK)
- After succeeding with the above, try pulling code from someone else's "git" repository and merging it into an Android build tree - and getting it to build correctly.
The above looks like a pretty short list - but it represents many, many hours of effort. Good luck.
bftb0
** There might be folks that take issue with that statement about ROM-building and Windows. They might tell you, "just download so-and-so's kitchen, and start building ROMs", it works fine under Windows." There's nothing wrong with that, especially because it can be satisfying seeing something of your creation actually running on a phone in a short period of time - but you probably won't learn very much, and when things go wrong, you'll be stumped about how to go about fixing things. The difference between a "chef" and a "developer" is that the former merely assembles together pre-built executable programs and libraries - whereas the latter understands not only how to go about building those things when the sources are available, but also has the opportunity to change them.
Lucky for me that I'm a Slackware guy. I'd much rather learn the system then just have a pretty GUI that does it all for me. That's half the fun of it.
Thanks for the advice, I'll have to try that whole bit out and see where it gets me. A weekend project awaits!
Hello All,
My question is whether the reverse-engineering of iOS's API is being looked at as an option any time soon. I would be interested in something similar to Wine (Wine Is Not an Emulator), which is a reverse engineering of the Win32API and allows you to run Windows .exe files natively in Linux or Mac OS. I am aware of iEmu (and it's unfortunate suspension).
However, my interest is not in getting iOS itself running on my phone, but instead I would like to run the apps themselves. I'm pretty sure there isn't currently a project on this. If there is, can you inform me of it?
If there is not, I would like to discuss the difficulty of implementing this. I could definitely be an aid in starting a project of ths nature.
Here are some things about iOS's apps I am unfamiliar with (I am aware that this specific section of the post may be more fit for the iOS forum):
Does the Obj-C code compiled for iOS resemble native ARM code (the iPhone chips are ARM to the best of my knowledge), like how C++ would be compiled, or does it resemble something more like C# or Java, compiled into bytecode that is executed by a library?
Compared to the size of the .NET framework or Win32API, how big is the iOS library?
Has a successful program been created that can run Obj-C code?
Would this have to be worked from the ground up (figuring out how Obj-C compiles in the first place), or has there been some effort already mounted similar to this?
I am aware of the extreme difficulty in implementing this. However, I'm sure this was thought while planning Wine or Mono. I'm not even suggesting this be made, but I'm simply asking on your opinion on the general difficulty (can it be done).
Thank you,
- κυριακος
kupiakos42 said:
Hello All,
My question is whether the reverse-engineering of iOS's API is being looked at as an option any time soon. I would be interested in something similar to Wine (Wine Is Not an Emulator), which is a reverse engineering of the Win32API and allows you to run Windows .exe files natively in Linux or Mac OS. I am aware of iEmu (and it's unfortunate suspension).
However, my interest is not in getting iOS itself running on my phone, but instead I would like to run the apps themselves. I'm pretty sure there isn't currently a project on this. If there is, can you inform me of it?
If there is not, I would like to discuss the difficulty of implementing this. I could definitely be an aid in starting a project of ths nature.
Here are some things about iOS's apps I am unfamiliar with (I am aware that this specific section of the post may be more fit for the iOS forum):
Does the Obj-C code compiled for iOS resemble native ARM code (the iPhone chips are ARM to the best of my knowledge), like how C++ would be compiled, or does it resemble something more like C# or Java, compiled into bytecode that is executed by a library?
Compared to the size of the .NET framework or Win32API, how big is the iOS library?
Has a successful program been created that can run Obj-C code?
Would this have to be worked from the ground up (figuring out how Obj-C compiles in the first place), or has there been some effort already mounted similar to this?
I am aware of the extreme difficulty in implementing this. However, I'm sure this was thought while planning Wine or Mono. I'm not even suggesting this be made, but I'm simply asking on your opinion on the general difficulty (can it be done).
Thank you,
- κυριακος
Click to expand...
Click to collapse
Hey and welcome to the forum's I would like to know this as well but I do not know any project and any that gets started and gains popularity gets chased down by Apple's legal team quite quickly. I have my doubts that this could happen (I would be glad if someone could prove me wrong) because iOS and its apps work on 12 devices and Android has hundreds of devices, most with different hardware. Windows apps are built for variable hardware, likewise with Linux and now Mac OS X. Sorry but as much of a pessimist as I seem I do not think it's possible but I'd love to be proven wrong. (Can someone at least make a frigging Windows Mobile runtime)
Hi, I've been looking at running GNU Linux apps on a rooted android. device with modern hardware and I've yet to find a 'nice' way to run x apps with acceptable GUI performance. Currently I've tried the java implemention of x on android which is barely useable and various vnc - rpc intergrations running x11 using a virtual frame buffer which is much better but laggy.
My idea to solve this problem is to completely do away with the vnc etc.. proxying. that 8s hack the virtual frame buffer version of xorg so that the main pixel map surface is in ipc shared memory and use ipc to render this through the android api.
So is it possible to statically link the needed android libraries to allow abdroids ipc to work between a hacked xorg vfb and abdroids shared memory ipc to a native android app. Thus making high performance rendering with near zero memory coppies possible.
Secondly, and this would be a bonus, could I even get rid of ipc and a native android app by getting xorg on my root GNU Linux install to work directly with android graphics and UI apis. This would be ammazing.
Hopefully ipc is at a kernel level so it may be possible to just port the needed parts of android to GNU Linux to do this if the statically linking method is known not to work.
Any ideas and suggestions, what do you think of this idea for intergraring GNU Linux x apps and android.
I really like this idea and I've been looking for something like this. You said you used the "X server" android app? I'm kind of curious on the performance. Was it laggy or just that it wasn't fully what you expected?
jthree2001 said:
I really like this idea and I've been looking for something like this. You said you used the "X server" android app? I'm kind of curious on the performance. Was it laggy or just that it wasn't fully what you expected?
Click to expand...
Click to collapse
Currently I'm running xrdp and tightvncserver in a gnu/linux environment (using inode linking not chroot) and xfe as the windows manager.
I connect to this from android using a rdp client.
The main issues appear to be very slow performance on graphics updates, visably slow, which I put down to the overheards of running everything through vnc/rdp - over sockets - mem coppies, compression (which I should turn off to see if it helps) encryption and all that stuff that goes along with rdp and vnc that's not needed if you use something like shared memory and blit to that.
Performanc of the apps in xfe &co, for instance libraoffice or eclipse etc.... seems to be pretty good, so that's not the issue, just the graphics.
Running a Asus transformer infinity T700
my current messing arpund has been trying to get the Android NDK to compile and run on ARM, which in theory should be no problem so long as it doesn't rely on x86 machine code to do the job (which I doubt).
idky google locked down the architecture in the builds and didn't just leae it as any old gnu/linux or whatever and let the person making the build tweek any bugs, instead of having to hack googles custom build system for building the toold chain to for a specific architecture.
floowing some rough profiling
jthree2001 said:
I really like this idea and I've been looking for something like this. You said you used the "X server" android app? I'm kind of curious on the performance. Was it laggy or just that it wasn't fully what you expected?
Click to expand...
Click to collapse
Ok, I did some crude profiling using the setup
tightvncserver
xrdp
and xrdp client on android.
the major bottle neck was the rdp client on android which made my testing cpu limited since it was maxing out cpu usage. I beleive this may be due to a bug in Android on my tablet relating to non opengl es graphics..
anyhow I got some more usefull data
xrdp was typically sitting at around 40% cpu and all it's doing is taking data from tightvnc and shunting it over rdp to the client.
next on the list was the vncserver using typically less than 30% cpu.
I think this shows there is clearly a lot of overhead (based on the 40% cpu xrdp was using) of using a remote desktop protocol over sockets that should be easy to mitigate by using shared memory.
I also tried a different setup
tightvncserver
and a vnc client on android
taking rdp out of the loop
again the android client made the tests cpu limited but perforance was much better.
This VNC client is open source, so my next step is to create an opensource project and modify the VNC client so that the user input is up to scratch and look at using opengl for graphics (assuming that's where the bottle neck is) so that it's not longer cpu limited.
Once that is done (which should also failarize me with the VNC protocol and the client code).. I can look at replacing the graphics part of VNC with a shared memory buffer, but keeping the user IO over the existing VNC protocol as that makes sense...unless that also becomes a major issue.
That also leaves me some way of sending additional data back and forth without having to do it 'all' via shared memory which would be much more of a mission
in theory there shouldn't be any need for any kind of complicated mutexing between the android client and the x server sine the x server will be all but write only and the android client always read only.
on a side note,
running java linpack on android I get about 50mflops per cpu
with disk io I get about 1gig per second cached reads.
so some crude math would give me 250mega words
my screen is 1920 by 1080 (well actually 1200), but we'll call that 2k by 1k, or 2 mega words.
so a theoretical performance into the high tens of fps seems quite achievable, which is much bettern that the 5 or so tops that I'm getting atm by an order of magnitute.
having a quick poke around, mostly related to my xorg wows (that is it complaints about no tty device when starting up. it seems that it's not too difficult to get xorg running using a frame buffer driver after a few android services have been stopped. So i'm not sure if this is still needed or not.. IPC betwen gnu and android is still an interesting project.
So anyhow, I'm going to try and get xorg running properly, there are even tegra 3 drivers for xorg too, so in theory the performance should be substantially better than anything an ipc hack would be able to achieve.
Hi all
Does anyone know if I can run kde-based software on the developer alpha of Ubuntu for tablets yet please? Not expecting reliability, just want to do some child user testing of the edubuntu suite on tablets.
Thanks
Chris
Currently you can't and probably neither in the near futur 'cause you need an X Server for that.
And there is no X server on ubuntu touch.
Huge thanks, that is really useful
Hempe said:
Currently you can't and probably neither in the near futur 'cause you need an X Server for that.
And there is no X server on ubuntu touch.
Click to expand...
Click to collapse
After some research on your reply I've a couple questions. Does it mean the Unity interface doesn't need X-server? Or are they just using a temporary workaround until X-server is implemented?
And does this apply to both Ubuntu for Android, and Ubuntu for tablets?
Huge thanks
Having done some further research I've made my decision - thanks hugely for providing the missing link in my knowledge. What follows is my best interpretation of the rumours.
Currently in place of X-server is SurfaceFlinger, ("because X-server uses 30 yr old code" - Canonical). Canonical publicly dabbled with using Wayland until mid-Feb, then decided to create their own revamped display server from scratch, called Mir, which they seem to have been working on since mid last year, and are trying to get GPU vendors to support, written to run across all devices and to meet the needs of the Unity interface, and written in Qt/QML which is what they want native apps written in.
Bottom line for me, is that the technology is still right up there in the clouds and nowhere near decided enough to base my business strategy on. Also, Ubuntu for tablets seems a pretty thin version of Ubuntu anyway, so Edubuntu was never an option and I'm unlikely to be able to leverage much from Ubuntu's Open Source libraries anyway.
Like others, (see the comment on jonobacon.org below), I find it frustrating that the wealth of code written for Ubuntu is no longer usable, but I reckon this is probably necessary to squeeze the most out of every single CPU cycle and milliamp. Ubuntu for tablet is dead in the water if it kills the battery and performs worse than the established competitors.
Therefore all indications are I need to write for Android, keeping my options as open as possible to migrate. So it is now Titanium/UnityIDE versus HTML5, particularly assessing relative performance.
http://www.omgubuntu.co.uk/2013/03/canonical-announce-custom-display-server-mir-not-wayland-not-x
http://www.jonobacon.org/2013/02/21/five-ubuntu-touch-facts/ -- not the article but the comment starting "In that case, wouldn't it be better to port existing apps instead of...."
http://www.omgubuntu.co.uk/2013/02/canonical-working-on-new-display-server
http://www.phoronix.com/scan.php?page=news_item&px=MTMwOTM
Just to clarify.
1. There are plans to make a X-Mir compatibility layer that will allow you to run programs that require an X-Server to work with mir.
2. Not all is lost at the moment it just looks that way.
Only Graphical Userinterfaces are affected. Your commandline tools and libraries don't need to be changed.
3. If you are looking for platform to write apps for, well there is worke being done to let you run your QML apps (intended for ubuntu touch) on android.
So if you choose to make QML apps they can be or will be able to run on linux, mac, windows and android
Wow, huge thanks, I missed that.
Does this mean EVERYTHING Ubuntu without a GUI will work? I want to run a NodeJS server. How likely is it that it will work perfectly now? How likely is it that it will work perfectly in the (nominally October 2013) release? (Sorry, just give me a keyword and I'll go off and do my research.)
Is Canonical planning to get X-Mir into the next ~Oct release?
My other query was whether QML on Android would perform as well. For others interested, it looks like it works directly with the Android SurfaceFlinger, bypassing the Dalvik VM, so performance should compare with native Java code.
Huge thanks once again
Chris
Sources:
http://www.youtube.com/watch?v=TEkubKZaUt8
http://victorpalau.net/2013/01/25/ubuntu-qml-todo-android-vs-ubuntu/
Download:
W10ANDW11-NETWORK-TCP-DESUBOPTIMIZATION.ps1
Run script as Administrator!
Background:
Microsoft's TCP mess, how to optimize in Windows 10/11
[German]Microsoft has made a few mistakes in the TCP implementation of Windows 10 and Windows 11 that severely limit the possible performance of TCP/IP connections. A blog reader brought this to my attention and immediately pointed out ways to possibly optimize something like this. I'm going to pres
borncity.com
Hi!
I was checking the script and the optimizations they are already implemented on my mod windows images!
Old stuff that you can find on Google and some one get togheter on PS script.
Some of the optimizations in there doesn´t help to much, i try it.
One optimization in there that real do some boost and we can feel it is disabling Nagle’s Algorithm ( TCPNoDelay=1; TCPAckFrequency=1), you can add TcpDelAckTicks=0 it will help.
I have some of them in my batch.
But still a good tool.