On 08/22/2011 01:59 AM, NilesH wrote: > BASIC IDEA: > In embedded systems, existing bootloaders run in three stages. But the > main focus should be on the vendor bootloader and the third stage > bootloader. U-boot and Barebox are examples of third stage bootloaders > that provide a rich set of features. It propose to eliminate the third > stage bootloader by combining its essential features into the vendor > bootloader, creating a single stage bootloader.
Just a comment on this. While improvements to bootloader performance are helpful, the kernel and bootloader are not the difficult problem areas in Android boot time. Techniques for achieving boot times for the bootloader and kernel in the 1 to 2 second range are well-documented (see http://elinux.org/Boot_Time for resources). Of course there's always a good amount of effort required getting the specific solutions working on your hardware ;-) However, the big problem with Android boot time is the user-space portion of the boot. The overall init system, involving loading and initializing multiple daemons (some with networking waits), as well as initializing zygote and preloading classes, and doing the package scanning and manifest/security validation -- these are where the big time is spent in Android boot time (in a cold boot situation). These are, IMHO, more difficult to work on, but have the potential for bigger impact (across a wider variety of platforms). In case people haven't seen it, there is some information at: http://elinux.org/Android_Booting Just my 2 cents. -- Tim ============================= Tim Bird Architecture Group Chair, CE Workgroup of the Linux Foundation Senior Staff Engineer, Sony Network Entertainment ============================= -- unsubscribe: android-kernel+unsubscr...@googlegroups.com website: http://groups.google.com/group/android-kernel
