On Thu, Oct 15, 2009 at 00:17, vamsi android <[email protected]> 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. > >> >> > Regarding real time support in android, basically most of them are >> > concentrating on Application base of Android, but as Android uses >> > regular >> > kernel, where it gives average performance and its not optimized for >> > real >> > time, we might see some performance issues on Android. Practically I >> > have >> > not checked any hand held devices which uses this Android and how it >> > performs, but if Android kernel can be made real time to some extent, >> > then >> > we can atleast see better performance right? >> >> 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.
Are you specifically needing to work with RT patches and PI enabled futexes for userspace? Sean > > ---> 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? > >> 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!! > >> >> good luck, >> >> greg k-h >> >> > > > > > --~--~---------~--~----~------------~-------~--~----~ unsubscribe: [email protected] website: http://groups.google.com/group/android-kernel -~----------~----~----~----~------~----~------~--~---
