Re: Super Fast Boot of Embedded Linux: 300 ms from boot loader to shell
Hi, Marco Stornelli a écrit : Il 13/04/2011 16:53, Constantine Shulyupin ha scritto: Thank you Marco for your feedback. I've added summary of used optimization method: • Reduction of kernel and filesystem size • Kernel features: naked boot, initrd without compression • Optimization of NAND flash interface in boot loader • Boot time was measured with utility tstamp • You can find more detailed list of methods at http://elinux.org/Boot_Time • Techniques for improving embedded Linux startup time, presentation: http://www.makelinux.com/emb/fastboot/MontaVista Actually, detailed implementations of optimization methods are described in numerous documents. I really know. I was talking about *your* optimization method, but if I well understand you've just applied a list of well known methods. Not to say such case are not interesting : loading a linux kernel with only a serial driver, a ramdisk and a shell as init doesn't reflect reality. In real product what you want if fast user interaction (sound, mounting big filesystem with user data, lcd display, ...) Matthieu -- To unsubscribe from this list: send the line unsubscribe linux-embedded in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 4/6] Add support for LZO-compressed kernels for ARM
Albin Tonnerre a écrit : On Fri, Aug 07, 2009 at 01:50:03PM +0200, Matthieu CASTET wrote : Albin Tonnerre a écrit : On Fri, Aug 07, 2009 at 11:36:56AM +0200, Alain Knaff wrote : On 08/07/09 11:24, Albin Tonnerre wrote: Regards, Could it be that the patches that remove division (zutil.h and inflate.c) have somehow not been applied? Indeed, they've not been applied. However, I'd rather try to understand why exactly this is an issue when compiling with -Os and not -O2 instead of working around it by removing the divisions. Look at the generated code. Arm doesn't have division instruction. May be at -Os gcc emit a call to the software division, but at -O2 it manage to optimise the division (transform it in shift, inline some builtin, ...). Yes, I figured that out. What I don't get, though, is that it fails while the software division symbol (__aeabi_uidivmod here) does seem to be provided by libgcc. AFAIK we don't link the kernel with libgcc. That's why the kernel provide __aeabi_* in arch/arm/lib -- To unsubscribe from this list: send the line unsubscribe linux-embedded in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCH [0/3]: Simplify the kernel build by removing perl.
Rob Landley a écrit : On Friday 02 January 2009 03:26:37 Arkadiusz Miskiewicz wrote: On Friday 02 of January 2009, Rob Landley wrote: Heh, I believe all three scripts run under dash and busybox ash. (The timeconst.sh one needs 64 bit math which dash only provides on 64 bit hosts, which is a regression from Red Hat 9 in 2003 by the way. With dash 0.5.4-12 (from debian sid), I seems I got the 64 bit math for 32 bit hosts : $ uname -m i686 $ dash -c 'echo $((132))' 4294967296 Matthieu -- To unsubscribe from this list: send the line unsubscribe linux-embedded in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
