On Wed, Oct 14, 2009 at 10:17 PM, vamsi android <vamsi.andr...@gmail.com> wrote: >> > Hi, >> > >> > Regarding Realtime patches, I was successfully able to patch it on >> > normal >> > linux kernel, but was not successful when I integrate it with Android >> > kernel. I was able to patch and compile it, but am facing while loading >> > the >> > android system. I get some errors while loading real time modules. >> >> What are these errors specifically? > > ---> I was trying to patch RTAI and patched successfully. When I > tried to start android, RTAI patch initialised successfully and it started > its scheduler part, and when it was trying to load HAL module (RTAI mounts > HAL module) but was getting stuck there stating waiting for response and > hence android is stuck.
I suggest asking the rt kernel developers about this. But note that the locking model in the Android core is much different than the rt kernel patches are expecting, so problems might happen with the interaction. >> No, not at all. A real-time system is slower performance than a >> non-realtime >> one. Please read the documentation for what a real-time kernel means >> for details on this. > > ---> I was doing research on real time kernels and what I found is > - Linux scheduling algorithms are not designed for real-time > tasks. > - context switching is not predictable, it might take longer > - Timer resolution - 10ms and low priorty tasks still runs and it > will make > wait a high priority task. > So, there are few disadvantages of linux kernel which are > made sure in Real time OS. with this tuning of kernel, > atleast fault tollerance should improve and performance a little > right? No, not really. Please, run a "real-time" kernel and look at the performance numbers. A real-time kernel is much slower overall. This is exactly what you do not want to have happen for a system you want to get the best performance out of the hardware. >> Running the rt kernels will just slow down your android system, which is >> not what I think you want it to do. > > --> Regarding Android system performance, at present when we compare > iphone performance and G1 performance we can clearly see the > difference. So, what I was thinking was to make android > performance better and comatialble to iphone. The speed with which > applications are loaded, and accessed are not matching with > iphone!! That is because the hardware is vastly different, you are comparing two different things here. Why would you expect the performance to be the same? good luck, greg k-h --~--~---------~--~----~------------~-------~--~----~ unsubscribe: android-kernel+unsubscr...@googlegroups.com website: http://groups.google.com/group/android-kernel -~----------~----~----~----~------~----~------~--~---
