Ext3 or Ext2?

Why all images uses ext3, if all the guides cite as better alternative to flash memory like SD cards, the use of ext2?

Ext2 is very fast and light and dont read and write all time to flash memory.

maybe ext4 would be best. its allocation methods should reduce
fragmentation.

it can also be run in nojournal mode, if you want to minimise writes.

sam

There is very little difference between ext2 and ext3. Journalling is a good thing - even on flash filesystems. The main problem is with a file’s last access time, or atime which is updated everytime a file is read. This causes the whole block to be re-written, after a few million file accesses and the flash memory will be getting worn. Fragmentation really isn’t an issue in flash memory as the access time is pretty static and there isn’t any extra delay when moving from one area of the disk to another…

Well, that actually is not a problem since it can be easily disabled
at mount time. All file systems on my BeagleBoard are mounted with
noatime flag.

I've also put on ramdisk all log files and other temporary files
(i.e.: /var/lock, /var/run, etc.) reducing dramatically the number of
writes on the flash memory.

Regards,

Pietro Pizzo