Which filesystem?

[dsavard]

I just received my 1GB Lexar SD Card and I would like to know which filesystem is preferrable to format it?

I don't plan to use this SD card in any non-Linux device, so I don't see any need to stick with the FAT format, unless there is an obscur reason for such a choice.

I am planning to eventually switch to OZ or at last experiment with. Is there any problems flashing from a SD and/or CF storage other than FAT?

Which filesystems are supported? Any problems when suspending/resuming?

So, I am seeking for you advise.

[zenyatta]

If you want to switch ROMs you do need a FAT-formatted card for that. For the 5500 it has to be a CF card, I don't know about the 6000. If you flash from SD the first partition on your SD card will need to be FAT (but you can have multiple partitions - check ZUG howtos).

There is one good reason to have a non-FAT filesystem: FAT does not support symbolic links (making the computer believe a file is somewhere when in reality it is somewhere else). These are necessary for some programs' function and such programs cannot be installed to a FAT-formatted card.

As for which filesystem is the best: JFFS2 was developed specifically for flash cards and has some nifty features (uniform wear distribution, write minimization). I believe OZ supports it though I'm not sure (and I definitely don't know about other ROMs). The other choice is ext2 which is definitely supported in OZ and elsewhere.

z.

[el_borak]

As for which filesystem is the best: JFFS2 was developed specifically for flash cards and has some nifty features (uniform wear distribution, write minimization).

No, jffs2 was specifically designed for writing to embedded flash, not to removable flash cards.  These already have their own levelling and wear algorithms.

[zenyatta]

Thanks for the clarification. One learns something new every day

[nexxusone]

I'll be receiving my 1GB SD card shortly. I'm really considering Ext3. Are there any reasons why I should definitely NOT do this? I plan to use my Z largely for emergency support situations, and waiting 20 minutes for fsck is something I'd rather not do.

Thanks!

[thesing]

AFAIR it is not good to use a journaling fs like ext3, because it writes quite often to the same sectors.

[iamasmith]

Actually I prefer ext3 although if you have a card large enough to accomodate the loss with the minimum journal size reiserfs (again if you have a module/kernel support) may be worth a look.

Judging from the information that kopsis posted regarding write spreading technology present on SD cards I don't see that having a journal based fs is cause for concern in wearing out cards prematurely.

ref. How to format a CF or SD as ext3 under Cacko, and why ext3 is better than ext2

I would much rather my data was intact and if I do crash the Z the journal will pick that up. I have a 512Mb SD card at the moment that I have run for quite a while on ext3 and it's been great, I'm waiting for a 2Gb SD card to come through any day now for about 1.5x the price I paid for the 512Mb card so I think I'm much more likely to change the card before it wears out.

Now you may think I'm more extravagant than most with the card purchases but wear times are being quoted in the range of tens of years because of the write spreading technology so I think my philosophy on cards is probably safe for most people.

- Andy