Andrew Daviel wrote: > By default, SD cards come preformatted as VFAT, as does the internal SD > on the N810. If you want to mount them on Windows, they have to stay that > way. But you can also reformat them with a Linux file system, or create > multiple partitions. > > One problem with leaving the card as VFAT is that you cannot create > symlinks from the root filesystem. Also VFAT does not support > attributes such as ownership or execute bits. The default mount is > /dev/mmcblk0p1 /media/mmc1 vfat rw,noauto,nodev,noexec,nosuid,utf8,uid=29999 > 0 0 > i.e. belonging to "user" and you can't execute programs. > > The kernel on the N810 (OS2008) supports ext2 and ext3 file systems. I > just reformatted both my internal and removable SDs as ext3 (also > created a swap partition on /dev/mmcblk1p2) and it seems to work as far > as I can see. > > What is the best available F/S for flash ? And what options ? > I have set noatime as Nokia has on / (don't write the access time) > > I saw an interesting webcast by Mentor Graphics where they were talking > about designing a new filesystem especially for flash, which would be > 100% fault tolerant to loss of power and would minimize write cycles etc. > They mentioned problems with FAT as not being fault tolerant and not > supporting large files. Also that flash may have a limited number of > write cycles per bit (around a hundred). (so maybe I should use ext2 not > ext3 to minimize journal writes, or put the journal on / (whataver > technology that is... it's mounted jffs2.) > > With regard to limited write cycles, SD cards automatically and internally do wear leveling (that is, writing to place 0 on the drive might never be the same place) to counter that effect, so that's why FAT works without burning out cards writing the FAT every time you change something. When you have a "memory technology device" - aka, just a flash chip directly attached some how, not through SD (think the internal 256), then a file system like JFFS (which the Nokia devices use) does compression and wear levelling at the FS level.
RYan -- Ryan Pavlik www.cleardefinition.com #282 + (442) - [X] A programmer started to cuss Because getting to sleep was a fuss As he lay there in bed Looping 'round in his head was: while(!asleep()) sheep++; _______________________________________________ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers
