On Tue, Jun 30, 2009 at 10:40 PM, mqy<meng.qing...@gmail.com> wrote: > My test with omgps running shows no failure, with 26954 image files. > You can add a swap file /partition then test again, to see if limited memory > causes this problem. I've watched with `vmstat 1`, seen limited memory > usage. > > Here is my clues: > > #1: max current of usb power supply is 500mA, with heavy CPU load, uSD card > may not get enough power then fails to work. > > #2: Many people experienced the "lose partition problem" including myself, I > can remember somebody asked that "why GPS hurt uSD card?".
Ok, I lied a bit. I only tested with tangogps. But, it was reproducible. If the device freezed or I removed the battery, many tile maps got unreadable. I couldnt even list some directories or cd into them! (it rules out heavy CPU load, and not getting enough power) I already wrote about it about a month ago: http://lists.openmoko.org/pipermail/community/2009-June/048997.html So the problem really comes about the insane 75000 files (118MB). I would really like to tar, ar, zip, etc the dirs containing the invidual tiles. It seems an easy job! Would be much more managable, speed up a lot the file copying (copying many small files is several magnitude slower!). Current directory structure: OSM/11/1102/715.png OSM/11/1102/716.png OSM/11/1102/717.png OSM/11/1102/718.png We could simply create an OSM/11/1102.tar file, containing those invidual files. I bet it would be not slower. I could even imagine some speed boost. Remember accessing invidual files on a sd card takes time. A lot. You can try it for yourself, copy to a pendrive your ~/Maps directory. Now tar the dir (Maps.tar) and copy that singly file to the pendrive. The result is something like 40sec compared to 6-7min. So please consider to implement this on-the-fly untaring capability. Thank you, Laszlo _______________________________________________ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community