Hi Neil, > Am 03.05.2016 um 13:12 schrieb Neil Jerram <[email protected]>: > > On 23/04/16 10:04, Neil Jerram wrote: >> Ah great, thanks. So, to be clear, you are recommending 4.5? [1] >> (Understanding that this is for experiments like mine and possibly not for >> full phone operation.) >> >> [1] >> http://git.goldelico.com/?p=gta04-kernel.git;a=shortlog;h=refs/heads/letux-4.5 > > I've built letux-4.5 now; haven't yet tried to boot it. > > I notice, though, that it appears to require lots more disk space when > installed on the GTA04, compared to 3.7 or 3.17. Specifically, the > /lib/modules/`uname -r` tree is now about 200Mb, whereas for 3.7 or 3.17 it > was about 16Mb.
Well, it is the result of a compromise between goals. * one is that the Letux kernel shall support many different device (GTA04, BeagleBoard, BeagleBone, PandaBoard, OpenPandora, Pyra and more). * another one is that there are a lot of peripheral drivers (e.g. for external USB devices) that can be loaded on demand - and therefore we configure for a driver module. * and finally, the 3.7 kernel did configure many things into the uImage instead of a module. This makes the kernel boot faster, but is less flexible. So the result is a big set of modules - where many are not loaded and just sitting around on the root file system in case you connect a compatible device through OTG for the first time in 2 years... > > Is there something I can do to reduce that? Perhaps some global stripping > option? Or alternatively some big trimming of the CONFIG_* settings? You can either reduce many CONFIG options. But it is difficult to maintain (because every second Linux -rc introduces/removes/changes some configs). An alternative is to take the approach of the flash-nand script which tries to identify by lsmod / modprobe which module files have really been loaded and strips (well, does not copy) all others: <http://git.goldelico.com/?p=gta04-rootfs.git;a=blob;f=config/root/flash-nand;h=be52b64a22f01237f62c4d874cd32245f48269c5;hb=6ea2ef256dcb0b98482022ce87d2b18e0498dab2#l23> Another idea could be to define some rm /lib/modules/kernel/pattern* Generally I think the best approach is that the letux_defconfig compiles as many modules as possible. And distributions copy only what they need. Lukas is following this approach for the latest Replicant experiments. If you find a good solution for a general "strip-modules" script that can be run on the GTA04, please share! Thanks, Nikolaus _______________________________________________ Gta04-owner mailing list [email protected] http://lists.goldelico.com/mailman/listinfo.cgi/gta04-owner
